I have transfigured in almost 50% of my last 20 games.

I am enjoying it, but it may take awhile to create a suitable reply because there's a lot to unpack in your post.

 

The SL avatar regen's and the fs avatar can be healed from the font bonus. Only two ways I see an avatar heal

 

the fs avatars is one of my favorites, no one can hit the road like he can!

 

KF or split deck avatars can get regen through bond of vashal as well.

 

This is a bit of a tangent, but one of the things I think is interesting is that both Pox and Hearthstone have this same "problem," Pox has the advantage of fewer factions (8 vs. 9) and the ability to mix and match (even using all the factions, though it's generally sub-optimal to do so due to the Faction Bonus mechanic), and perhaps the largest difference in business model, the ability to trade cards. On the other hand, Hearthstone has Neutrals, cards which are usable (if not always useful) no matter what faction you choose.

All told, I'd argue that Pox has the easier time in dealing with getting cards that aren't in your faction (especially with trades). But at the same time, it feels like it's much easier to hop between classes in HS than it is to hop between factions in Pox. I'm not sure what the exact ratios would be, but I do think that it has to do with a couple different things:

Legendaries in HS are almost all Neutrals. So if you make a big investment in, say Ragnaros or Dr. Boom, you'll be able to use that investment in all the things. While you can obviously use ST (for example) Legendaries in whatever BG you wish (though Exotic Heroes are limited) it feels like you're encouraged to play ST more. That ties back into that Faction Bonus thing.

There's also the issue of Avatars, but loosely since DOG took over (the only reason I haven't gotten all the Avatars by now is purely personal preference at this point). While there's still a time investment to acquire an Avatar and then level it, it's not that much different from HS Class unlocks (Pox takes longer, not counting HS's cosmetics for particularly high level classes)

So I'm not sure how much of it is Faction Bonus, Avatar, or simply the huge amount of runes in each faction by comparison. Will HS have the same sort of "investment" with a larger card-pool?

That is, when HS releases it's 27th Expansion/Adventure will it be as difficult for players to hop between Classes as it sometimes seems for Pox players to hop between factions?

It's not a question I can answer easily, and (provided HS lasts long enough, which so far seems it might) I can likely only wait and see.

 

a lot if you want to be competitve