I appreciate this game very much, having been a player for a decade now I think I would be happy to pay mount skins or gliding skins etc. Early players wouldn't find the appeal of that which is understandable.
However, this game has given a lot and I am more than happy to give my money to a game I love, the base game is free (no subscription fee) which gives the first player to know if they like this or not. Expansions were recently on a discount that was dirt cheap as well.
I don't agree with you here, mainly because it would make more sense to put it in a new expansion it would be a better market strategy, and have it similar to a grinding way as the old skyscale way which everyone wanted! So people brought the expansion path of fire & living season 4 for that reason, which makes the expansion game even more appealing.
However, themed furniture/wall paper/really cool designed buildings makes sense to put it in the gem store OR prime gaming. Gw2 needs to continue creating new ideas for their game they would be open to their creativity more, and it would make sense to bring this in not only because it's a trend in games but there is a high player base that loves building such as Sims games that are cozy game players.
So I am happy with what the game is at and probably what they'll add in the future