??? There were some similarities because it was Marina, but I never found V/M and D/W to skate super similar styles. And "a lot of precise themes or powerful music" isn't really how I'd describe V/M's style. The most obvious difference of course would be that their programs tended to feature much more romance than D/W, which suited them just fine. Besides, V/M have always been a versatile team, especially compared to teams like P/C and C/L (not criticizing these teams, I like them both a lot). That's why they tend to excel in the SD. Of their FD's, I've seen a lot of fans list these as their favourite: Umbrellas of Cherbourg, Pink Floyd, Mahler, Carmen and sometimes Hip Hip Chin Chin. Pretty different styles in there.
Anyways, back on topic, I agree that every team shouldn't try to do the same style. It does get sort of boring. I think the issues with levels with the Russian teams are much more important than the style. The comments you hear from some of their coaches, essentially saying levels aren't real or are just politics make it look like they don't get it. And maybe this isn't actually true, but if the coaches don't get/believe in levels or whatever, that's a major problem. And also, I think the quality of the coach matters more than location. I don't know enough about most of the coaches coaching in Russia to make any judgements about how good they are, but it does seem pretty clear that Marina, Igor and the Montreal team are all great coaches, so if they are better than the Russian coaches, then there would be an advantage to working with them, politics aside.