Russia seems to be quite an interesting challenge. Militarily backward to start compared to powerful neighbors, and needs to tread carefully at first. But with good play and some luck, can rise to considerable power.
Actually, Russia is a monster in EU. In all campaigns I've yet played she has trounced all her neighbors and grown to alarming size faster than you can say 'cheese'. The only times I've seen her checked is when I've done it myself.
Muscovy actually starts with higher tech levels than Sweden and her infantry costs only 2 (nothing, compared to the 8 for Sweden and Poland).
Furthermore she has a great natural ally in Denmark that will incapacitate Sweden effectively for most of the game.
I have yet to play Russia myself, but frankly I don't see the challenge... Try playing Sweden instead; it will have you shedding tears the first years.
/Doomie