I've never given my wife a French Kiss and she still married me with out any tongue sugar. 
A french kiss is a great way to arouse her however by stimulating her lips mouth and tongue
But what about bad breath? Bad breath is a big turn off!
Yes halitosis is a real problem when kissing, but sometimes breath mints or brushing your teeth can help with the odor
It's my my breath it's hers. Should I just wait until she come at me with a kissy face and throw a tic tack in her mouth?
Tic tacs can help but i would recommend you encourage her to practice good oral hygiene instead