Hearthstone is 5 years old already and we’ve only been introduced into 3 different formats.
Standard, Wild and Arena.
What this game needs in my opinion is more formats with more diversity.
I will give the example of Magic the Gathering (the mother of all card games).
They have their respective Standard and Wild (Vintage) formats, same like Hearthstone, however they have introduced more like Pauper and Limited (among others) with different rules and limitations.
For anyone who is not familiar with them I will briefly describe them:
Pauper: Format that limits deck construction to only uncommon cards.
Vintage: Same as our Wild
Limited: Same as Vintage, with limitation / ban of OP cards.
Now, let’s think Pauper for a bit. We could have a similar format that could also split into sub-formats per rarity (one for rares, one for epics and one for legendaries).
We could have formats for basically everything: DK heroes only, Even / Odd decks only, Class specific formats (Druids only, Hunters only etc), Year of “XX” formats where people can craft decks from the full cycle of previous years.
Basically any idea of restriction / limitation could potentially become a playable format.
Even the exact opposite: Format that allows more than 1 legendary for example, or more than 2 copies of the same card (That would be problematic with the crafting / disenchant system though).
I guess you get the point though.
The game needs more formats to keep things fresh and interesting and to (potentially) attract more people.
Just think of Pauper for a minute. Only uncommon cards allowed. That would be a paradise for new players, as they wouldn’t get roflstomped by fully fledged meta decks - hence a better experience for them.
Or think about any other format, that would actually “filter out” players from Standard and Wild and “spread them out” to all sorts of different crazyiness that matches their gamestyle, gamestyle, etc.
Hopefully we get to see some diverse formats soon.