Kronos isnt that bad tbh. Nostalrius was ultimate with all the support and especially with the content timeline - that was something new and awesome, no doubt. There hasnt been such a professional and huge project on the private servers scene until Nostalrius.
Kronos is the nr.2, not comparable with Nost but still... it has good quality and it is supported by a big czech private server project TWINSTAR. They provide the whole range of WOW datadisks from Vanilla to Cata and have solid basements. You can be sure they will do their best to get Kronos working smoothly and almost bugless but atm they have a lot of problems - DDoS attacks, overhelming players demand which they cant handle with their current hardware (thats why the ques) and dealing with relocating their server hosting. But they will SOLVE IT SOON, you can be sure of that cause their other legacy servers are running on a very good quality level. I would give Kronos a chance... in a week or two tho...

Btw. playing GRIM DAWN atm and its rlly awesome. Owning Dialbo 3 easily. Love it - worth trying!