Not exactly. מ can also be "than". As in: יותר מקילומטר, more than a kilometre. Literally מדי means "than enough", but you can say things like גדול מאפס which means "bigger than zero", חזק ממני "stronger than me" etc. In Hebrew the "more" form of an adjective is the same as the regular form, we often use יותר but leaving it out is allowed, and so טוב מדי is "better than good enough", the same as טוב יותר מדי or יותר מדי טוב which is I think what I usually say.
Its "tsevet" not "tseva" and there no big difference between the two tsevet=team and kvutsa=group I hope that helped :)
I am sorry, I am really not challenging your Hebrew, but shouldn't this team be hatsevet haze whereas this is a good team should be ze tsevet tov?
I agree with Joel. Also, to say "this team is good too ", as in, this team is good as well, you would say הצוות הזה גם טוב Although I think you could put גם also at the end of the sentence or in the beginning, depending what you want to emphasise. I'm not a native speaker, but I'm pretty sure this is how it is.