it's quite impressive that with the kind of team they have, there's like 80% of the devs working on WotLK, 15% on MoP and 5% on Cata, and yet WotLK isn't working properly (AKA you can't kill Sindragosa or Lich King, which are the final bosses of the expansion), among much more ****.
So, WotLK isn't exactly receiving "profesionnal treatment". Focus? yes. But as long as this focus improves the expansion, not really.
I'll guess and say that Warmane makes money into the millions. Let's say 33k players have donated at least 10 euros, that's 330.000 dollars. To this add what some people donate monthly and those that donate more than 80-100 euros
I won't get in detail because I don't actually know about Warmane's financials or the size of the developper team, but if financials don't let Kaer Wolf hire or have more than just 2 developpers for Cataclysm and who knows how many for MoP, they should reconsider their business model and strategy. If you claim to be a WotLK server, then shut down Cata and MoP and focus on the expansion you have chosen as a priority.