Reign of Gaming

I agree, that will hit Zac's preposterously good early game right away will see a hit, but that just means doing a level 3 drive by of a solo lane stops being an automatic free 'let's see' kind of deal.  Most of my success playing Zac is attributable to the negligible risk of just hopping over to mid lane constantly because the jungle creeps stop being a health tax after level 4, and lets his already big lane presence be a nonstop one.

I wish I could literally beat this into the heads of some idiots I'm stuck playing with.  Multiple games, usually when I'm a top laner with teleport up or a beefy jungle Shen, I have the ability to split push and draw the attention of two opposing players (or rampage onto the inhibitors for free), and my teammates will simply start raging at me in all chat as they go about farming the jungle in isolated pockets without wards waiting to get caught out, while I'm off pressuring objectives and having to pick up an RSS or stack of wards as the principal damage dealer in order to create enough map pressure to keep us in the game, even though we've enjoyed a gold advantage the entire time.
As far as selecting between an inhibitor or baron when behind (when ahead, I'll take the inhibitor every time, and turn that advantage into huge map presence to force an unfavorable fight on them) - just keep in mind that whatever advantage is conferred from the Baron buff, it's only temporary.  If your team lacks the organization to convert that buff into map control or a couple turrets, then I'm back to feeling that the inhibitor is worth more from the free pressure alone.

I used to rock babysitter Malphite - mana issues galore, but against a bot lane pair that can't deal with that sort of harass, he's amazing.

I didn't think Lux support went anywhere - Crystalline Flask made it possible to be a relentless trading nuisance in lane, and Kage's building into Morellonomicon is simply excellent - with so many high CDR items that synergize well with her kit but are very affordable to aim for, she's still quite viable.  When I'm on fire with landing light bindings, it's not unusual for me to leave a lane 1/0/8 (has happened like 5 times).

Support fiddle works with the right team comps, that's not anything new.

Support Anivia, Support Heimer, Support Brand all have a somewhat relevant kit, but those three shine in other areas (and the inconsistency of skillshot stuns is nearly enough of a detractor).

Support Elise is also completely viable - a spammable skillshot stun, ranged poke, some sustain of her own, and % Health damage that doesn't require items.  With RSS and either GP10 support item she's still a fairly durable threat in her own right, and can still peel or initiate.  Not as good as solo lane Elise, but still good.

I really feel the rework could be as simple as operating Mantra charges in the same way that Rengar gets Empowered versions of his abilities after casting 5. All three other abilities have separate cooldowns for the Mantra enabled ability, and suddenly a lot of her lackluster, CDR dependent issues dissipate significantly. At this level, Mantra could be a learned ability at Level 6, because in essence it would provide a very LeBlanc like capability to duplicate a strong spell, but as a support Karma this could be astonishingly useful (or at least on par with Lulu's Ability to drop a shield with Wild Growth and Help, Pix!

This also creates that same ability to operate two unique spirit bonds - but with the mechanically simple drawback of still having to function as a common anchor yourself.  Alternatively, double spamming the spell onto the likes of Hecarim would be a triple bonus MS as a means of initiation nuking an entire team late game.  

Sure, the base values of the MS buff could use some help, but I think the biggest change to Spirit Bond could be that it applies a SLOW if applied to an enemy.  Zilean's Haste/Slow mechanic is quite similar, and there is a danger of a Mantra enhanced Spirit Bond being able to absolutely wreck an enemy's MS, but if the enemy is affected by HALF the MS difference on her W, that's a pretty fair exchange.  If that's coupled with my idea to allow a refresh of abilities by enabling Mantra, this gives Karma an exceptional ability to peel for an ADC that is completely independent of her ability to procure ability power.  From two mantra charges Karma would be able to slow, haste, shield, and heal.  The other effect of Spirit Bond (dot for enemies in the line) could be omitted, and instead any ally or enemy located in the beam would receive the effect of that spellcast could be a completely relevant capability in it's own right.

Some numeric reworks to pigeonhole her into a more support role would probably be welcome - what AP Mid Karma players exist would probably be quite understanding of a buff to the base value at the expense of AP scaling, simply because a CDR/Tanky build would be a usable alternative at that point.  

 The primary reasoning behind these is that there aren't really extensive changes required - her Q and E retain that very unique duality that fits with the personality of Karma, and then the W cast would gain that as well depending on the target of casting it.  No new resources are required, no new or unique mechanics or user inputs would be required.  Some numerical tweaking through the PBE environment could tune a lot of that, and make her a viable support with the ability to function as a utility mid-laner in a protect composition.

I agree that a base skill level is required in order to really want to try this out - if you want to run AD LeBlanc, you should probably be very good at both the ADC Role AND be intimately familiar with the mechanics of LeBlanc.

I couldn't have asked for a better example of this than the EU LCS W3D1 in the EvilGeniuses v FNatic game [SPOILER ALERT], where SoAZ, the solo top player for FNatic ran Blitzcrank.  Having both Blitz and Leona were utterly locking down champions, and basically assuring that xPeke on Katarina had a reset in each engagement.  While in the heads up matchup he got 'beat' by just over 40cs against Wickd at the twenty minute mark, Fnatic were able to dictate the playstyle throughout the game.

I would challenge both of you to put a gold value onto that utility.  Yes, Doran's items are very efficient items on stats, but more so what is the opportunity cost of delaying a primary build by 950 gold in order to have a bit more lane presence.

I completely agree that the utility value of lifesteal from the Vamp Sceptre or Bloodthirster was not given adequate attention for even the mid-game exclusive case where protracted teamfights or sieges allow the ADC to take small bits of damage and heal it right back.  I would, however, agree that the 10hp gained on hit from a pair of Doran's Blades is truly lackluster as the game progresses.  The only reason to stack the Doran's blades is for added survivability (this can be offensive - 160hp is at least another turret hit if one is looking to snowball their lane even harder).

I think in the example of a level 7 Caitlyn working on a level 9 ChoGath, there is no way to make that a fair fight unless the Cait's team is helping.  By Lvl9 that cho should be sitting on a pair of stacks with Feast, have ~40 AP or at least a catalyst and some armor, and have enough points into rupture that catching caitlyn with it would be a near death sentence.  

If anything, that example demonstrates that even mid-game ADC builds are relatively weak, and that the focus should still be on acquiring items, if possible, to scale more quickly into late game where that is a fair fight (Cho with 6 Stacks, Warmogs, ROA, Rylai's, and a Bulwark can still get shredded by a Caitlyn with IE/PD/LW/Vamp in an even fight with comparable gold.

If you're concerned with how closely it lines up to the BT and the 'Brutalizer and friends' builds at comparable points, don't be.  BT even unstacked is ridiculously powerful, and the brutalizer by itself is a bigger DPS jump than buying the more expensive BF sword. The power of IE comes from the added crit chance after the fact with a phantom dancer as a second item making the ADC a single target nuke.  BT/SS is a higher presence build for the mid-game, but the logical option is usually still BT/SS/LW which is is solid on champs with a good AD scaling spell if you went BT/SS.  For champions that will really rely more on autoattacking, once the IE/PD is finished they can be a dominant force if they're positioned right.