The general idea is good, BUT its a double edged sword, why?
Because as u know, not everyone is on the same skill level and gamewise level as certain ppl are. Some players do not understand or simply dont see arty being set or strike being thrown to opponents spawn or strategial position, which will mean that the fop who did everything right will suffer because of that one individual who just plays like a brainless chicken. Second one is that i have experienced couple of times as well and is very annoying that certain teammate will intentionally run into your arties and then complain afterwards, which means u will suffer reflective damage back each time purely because of his dumbness.
It also comes to nades, u would be nading enemy spawn, ur teammate with flamer or something else would run into that spawn, trying to flame opponents and die by your nade even tho he would probably see it before but decided to just ignore it. There are a lot of cases like that, when u check your idea from smiple view, its briliant and would definitely improve a lot in terms of teamkilling or team bleeding, but it would then need to be watched over admins as well, who would need to react quicker than usual if cases like above starts to happen because u can have very fast a big shit storm over situations like that.
I would still rather see on some maps heavy weapons disabled, specially sp_delivery_te, has no place for mortars, panzers or flamethrowers specifically, since the map is narrow and its just team bleeding allover the place.
U can obviously give this a go and see how it works, but this is just one of the flaws players will get once this idea gets live on server.