Like you Oulzac, CK II was my only Paradox game when I bought EU III last week. I had read some good reviews and wanted to see if I liked it before EU IV came out. I was in thhe middle of very good CK II trying to restore Rome when I became addicted to EU III. While CK II is character driven where you try to keep improving family traits to improve your duchy/kingdom/empire performance, EU III is based national perfomance where every decision affects every other decision.
My advice: EU III is like half price on the paradox store. I think if you give it a try, you won't regret it.
My advice: EU III is like half price on the paradox store. I think if you give it a try, you won't regret it.