I think legendaries is one of the few things Hearthstone does right. In a game where it's really expensive to get the most expensive tier of card, limiting them to one copy per puts a soft limit on how expensive decks can get. The feln cauldron argument is a straw-man, because all cards like that could just be rares and it wouldn't hurt much from a deck-building standpoint. Having those build around cards be legendary just makes those decks be a lot artificially harder to obtain and play, for very little good reason from a gameplay benefit perspective. From a money making perspective it makes it harder for people to obtain things they want without spending money so I guess that is good?
Capping Legendaries doesn't automatically make it cheaper as a result, it comes entirely down to how you design them. Renolock runs 9 Legendaries, more than any of the above listed decks, with a smaller deck size (albeit some of them are from adventures, for better or worse.) That's almost 25%.
It's not a straw-man, I'm not misrepresenting anything, it's the reality of things. Even if you did change the rarity, putting all the weird build-around cards down a rarity impacts drafting a fair deal, although I would personally like to see them be at an in-between rarity because getting playsets of legendaries to make gimmicky decks really is too expensive. Furthermore, you remove the ability to actually make Legendaries with significant deck-building sway. Shimmerpack? Nope. Queen? Leave. Marshal, Eilyn, LtF or Call? Gone. They only become meaningful if there's enough support elsewhere to where it's just a 'nice addition', and I think that removes a lot of agency when it comes to designing legendaries, something that should be there.
Finally, Legendaries are conductive to a better play experience, even if they may seem like nothing but a barrier to entry. They add excitement to pack opening, and they give players goals to work towards. They also let designers make exciting and splashy cards and make their appearance rate according in limited environments.
But at the end of the day the fact that you need to spend 12800 for a playset of something to play certain decks just makes those decks prohibitively expensive to play or even try out a budget version of. I really don't like it when games do this, and I don't think Eternal's in-game economy is generous enough to offset this.
Some decks are expensive, it's the reality of things. Sometimes, you'll have to work for what you want. There's still a lot of budget options for whatever you want. Aggro is easy to run budget. Someone hit master's yesterday with a Legendary-less control deck. The gimmicky mechanics of the game let you make combo-decks like Static Shock as well.
Speaking of, being better than Hearthstone is not something to be proud of. I got to play 2 Drafts last week and got like 30 new cards off of it, only one of those being orange and about half of those being green. Most of the cards I got are things I don't want, and I got so little dust from that entire experience that it's going to take a while to assemble decks I do want to play without putting money into the game or starting to seriously grind it.
This game has so much more stuff to get than Hearthstone did that the amount of extra stuff it gives you really doesn't compensate at all.
I don't want to just say 'git gud', but I'm pretty sure the answer is to get good at drafting. If you get even a single platinum chest, either naturally or randomly, the payout is pretty massive, since they cover 40% of the cost by themselves.
Furthermore, you are limited to exactly 1 rare/mythic per pack, and you cannot EVER get a better pack than that. That is ridiculously bad compared to a very large number of ccg/tcg games I've been playing, where the average pack is a little bit better and there is a chance for nut packs, which really just make your day when you get them.
You can get animated legendaries, but sure, you can't get the absolutely insane packs you're most likely not going to get anyway.
And because commons and uncommons are almost worthless, like severely bad to the point where Hearthstone would be ashamed trying to get away with this, 15 cards per pack because of this setup is very very little. Compared to other ccg games it feels like only getting 3 cards per pack, and it downright feels worse than most of the other things I've played and stuck with for long periods of time, and it is outright capped at a point where I just don't buy packs EVER. And drafts are kind of.... it's at the point where the amount of new content per time spent is very low and because I can't afford to make anything top tier ranked is just a chore to play.
>Hearthstone commons
>Not terrible
Sure, enjoy your 7 overcosted windfury minions.
Eternal's commons aren't the cream of the crop or anything, but they're perfectly respectable.