If the problem is about panzer players shooting 2 panzers, suiciding and repeating then instead of lowering the charge rate for panzer (which is impossible without making mortar unplayable since you have to update the whole class) you could just make it so when they die their bar doesn't immediately refill but rather stays at the same level than when he died. There is an option for that in jaymod, I remember it perfectly
Anyways what's up with this topic? Last time I played for a longer period the game was quite balanced, the only problem being unbalanced teams (like always) and mainly OASIS being a problem map. Maybe the problem is with the map (with it's 3 cramped ways to obj) and not with the server settings
Btw Samael I'm pretty sure it's possible to alter settings just for that map using mapscripts, I can do some testing with you this week & show you how if you're interrested

Hit me up on discord
E: Btw reducing rambo-medics' chargebars will just make them heal teammates even less xD I hope you realise that it's nothing related to server settings and 100% a gamestyle thing (which I don't condone btw)