Thanks all. Seems like Hilton is the choice here... Although it sounds like their footprint isn't so large either. I'm going to St Petersburg, Estonia, Latvia, Lithuiania, Belarus, Ukraine, Romania, Bulgaria, Poland and possibly Croatia. Oh and Turkey at the end.
I did a little research and I can get Hilton gold just by getting their credit card, so that's nice. Although I wonder how valuable the benefits can be if anyone can get gold level so easily.
I will look into Club Carlson further as well. I recall many Radisson Blu's in Western and Northern Europe. Not sure how many exist in Eastern though.
Thanks for all the advice. Def helped! I sure wish Starwood would stop their mad focus on China and expand a bit more elsewhere.