1) As mentioned, returning cleric stance is going to cause far more issues than it'll solve. IMHO It'll please a specific subset of high end healers, an unhealthy portion of which have already quit. On DPS complexity, giving back additional SB era DPS buttons from WHM and SCH would be a decent move though. As much as some people will complain about anything DPS related, I genuinely can't see any issue with WHM getting back Aero 3 and a tweaked Fluid Aura. Personally I'd go a step further with SCH and give them back their HW dots along with a Miasma II style MP/Movement dump. For AST, logs be damned, lets get back 3.2 era cards with a few tweaks to make the fodder more competitive such as switching it for a healthy DH buff.
2) I don't really see how this solves anything unless you really cut down healer's damage to the point where it's flat non existent? Healers are already at ~80% of the output of a tank as things stand. Dropping them to 50% is going to take them to ~3.5k each or 7k combined. That's still a very significant chunk of damage. Not to mention this would also make healers have an even more miserable experience in solo content than they already do. IMHO the only way SE could achieve the goal of preventing healer damage being a crutch is to simply make it so that healers can't afford to sustain their damage whilst also healing. Simply making nukes cost prohibitive isn't really the way to go as again, solo content will be a horrible experience. Rather adding a cost to oGCDs and tweaking the MP economy to match would be required. Would a more passive style of play that force standing around be an improvement? Ehhh I'm not really sure on that one. However......
3) Handily tying in with the previous point... If fights were designed so that they required strict bursts at specific windows but otherwise were generally laxer on the overall enrage timer, that could make the above idea less horrible. Enough to make it a stomachable direction? Still not sure but that's what forums are for
IMHO I think switching to a Savage ethos that focuses more on quick bursts of DPS rather than sustained damage across the entire encounter would be more impactful than hamstringing healers from their DPS kits in general though.