Its unlikely we get dual spec, so why not scale the cost?
P1 - 5g
P2 - 10g
P3 - 20g
etc etc all the way to p6 where it ends where it normally is at 50g.
Seems reasonable that the second we hit 60 we arent worried about 100g for pvping with our friends.
How much are consumables going to cost?

None since you either A farm them yourself or B play a healer which doesnt require any.
Exactly like gold? Ok.
Maybe they’ll add world buff vendors, and give toys that offer raid-wide consumes for free. And remove gold fees for everything like skills and mounts, and maybe they’ll make mounts account-wide, so if you get one on one character, you don’t have anything to farm or reason to play your alts.
Maybe they can remove other aspects of the game as well, making for fewer trade-offs and decisions to be made in the Classic gameworld.
There are a ton of QoL “features” they could add. Maybe they will.

Nope, wouldn’t want any of those because those make no sense at all.
Id simply rather farm a 1 time fee of 1000g and get to respec when in rested areas vs paying 100 - 200g a week for 12 months just to get to enjoy my class.
Of course not. Only the thing you personally want from a future expansion makes sense. Other things from future expansions you don’t want. You probably even think that what you want is “good for the game” and anything you don’t isn’t.

How about respecs are just flat 10g the whole time? Naxx is when consumables are the most expensive and become absolutely required, and therefore when 50g is the most painful.