I'm strongly in the camp of: each year they should release a Phinny/Mangler clone + an experimental server. In that context I think Vaniki is fine, on top of that I actually like the idea of a level locked server as well. But I think the level locked where they are putting you -10 levels below the norm is weird and probably adds a lot of wrinkles and unpleasantness that is unnecessary.
When I'd speculate on a level locked server previously, I always imagined they'd follow the level lock order that actual EQ followed: 50, 60, 65, 70, 75 etc. Within each of those level ranges you would then be able to do whatever content you were capable of completing.
Anyway, I think neat idea, some specifics about it are not good and probably will also create a ton of work for DPG down the road. I also would agree Vaniki won't get much interest--the main reason I say there should always be a Mangler clone is a large % of the population is simply not interested in anything if it isn't cycling through Classic-->Velious over and over again, so they just leave too much money on the table by not offering that annually. The experimental server, if they continue the approach of marrying experimental server with vanilla, will probably suck sometimes and not be worth playing, but I still think it's a good thing for them to put out the experimental servers. Quarm wasn't a big success from their perspective and Vaniki probably won't be either, but I think Mischief/Thornblade were huge successes and I personally rate Selo as a huge success--even though it had less people than Mangler it still had a robust population until WoWC came out, with like 10-12 raid guilds initially and 7-8 still active for a while. It also was probably one of the best play experiences I've had in EQ.