New expansions and new servers

Hey all, i am currently playing Wotlk on the lordaeron server and i'm just loving it, but i also wanted to try the new Legion expansion.
So my question is, will warmane eventually release some of the new expansions or are we only going to have the 3 we already have(wotlk, cata and mop)?
Cause i would really like to try them out but i haven't read anything about a new expansion here on the website.
And my other question is, why don't the cata and mop expansions have a 1x realm like lordaeron in wotlk, cause i wanted to try them aswell but the characters level up so fast that you can't actually enjoy anything in the game but the end content, because you can get to lvl 90 in a matter of 2 or 3 days and i think that the lack of diversity of servers is holding back the player base when compared to the player base wotlk has, aswell as taking the fun out of the expansion itself.
Thank you for your time,
Strangerunderurbed

Not soon, but we never said we were done, not until Blizzard is.

Cataclysm and MoP have fairly low player base compared to WOTLK, there is no point in splitting their population which fits best in an only realm.