Now, from my experience (which isn't saying much compared to the other Vice players around here), don't worry about drive cancelling anything when using Vice outside of HD.
Mayhem (tackle) is not safe on block regardless of your setup. Focus on mixing up your grabs/low pokes/overhead instead of blockstrings, since her moves aren't really optimized for that utility.
If you really want to use meter, you can do combos involving EX Decide (arm grab) which basically sets up combo loops till you run out of meter. More often than not, you can be doing cr.B, cr.B, s.B, qcb+A~qcf+A/C *optional supercancel to Overkill*, which does decent damage off of a poke confirm without having to use meter (if you chose not to Overkill). If you land an overhead, you get a free EX tackle to tackle-splash juggle. Ending with a splash is usually a positive for Vice since the opponent can't safe fall (roll recover), which lets you set up your oki: dash low, dash throw/command throw, arm grab, splash, empty jump/jump-in, bait something, etc.
You'll really want to save meter for EX arm combos or EX tackles to break through stuff though. Vice is limited in options when she has no meter, so keep in mind that she should be saving it for either big combos or to get herself out of defensive situations.
EDIT: crossed out incorrect information as stated by Kane317.
