Well, you asked "Is Vice's tool overpowered?"... and since the answer is pretty much "No", the answer ends up being "here's how you work around it!" which just happens to involve, in this case, your style of Ralf play. It would be best to be continued in his own thread, though.
Back to Vice, her EX Decide uses meter, adds hit scaling (even though it does no damage itself), and has a slightly tricky timing window. The possible follow-ups are also kinda limited (compared to, say, how Takuma's Kyokugen Houken (Or Hougeki, as it's called on Atlus' site) can allow you to land a hop attack after landing his "hitstun grapple".
It gives her an easy way to land HD combos (kinda), sure, but she also has some of the weaker HD combos around, to the point where they're getting a potential BUFF on console release (allowing her to use the stronger variety of her "Mayhem" tackle in her HD loop, to allow for greater damage). So, in the grand scheme of things, Vice using HD to kill an opponent, if she / the opponent is not the last, is doing less damage than if anyone else on her team did it. That's pretty faiir.
I like to learn on my own i hate using advise from otha people its not right to me and it takes the fun out of learning
As a person who wanted to live with fighters this way too... I warn you, it's a bad idea. I went through years nof NOT knowing things, due to not seeking out certain details and tactics... and all it lead to, was me looking back over years of play, wishing I knew to get certain things down BACK THEN, rather than learning them in a clump once I fight stronger opponents.
For example, the GGPO 98 Players really showed me how powerful MAX mode is in that game. I never cared for it back in ACTUAL 1998 time playing, so most of my GGPO matches were spent feeling like a heavyweight fighter in the middle of a gymnastics competetion; They ran circles around me, and I couldn't do much of anything to compete.
It's fun to learn on your own... but it's more fun to practice your character, and know that you can employ everything about them, rather than work off a self-gimped list of techniques.