there is already a mod out doing exactly that , and while it does help for starting mages it judst becomes very unbalanced at high lvls ; my lvl 36 mage can insta kill a a overlord with a dualcasting incinerate on expert lvl
you only have to throw a few fireballs in a room to clear it out at this lvl with little or no risk for your self
I don't think balancing destruction is done so easily
Response to bolded: no, it's not, as I found out while doing my own Destruction mod.
I implemented higher bonuses than that in order to keep lower spells viable later on, but ran into the 'Incinerate Problem' in the process- lower-tier spells just cannot keep up if you can chain the higher-tier ones as well. Adjusting it is going to be a pain, though, as there's no good way to allow the lower-tier spells to remain viable that doesn't screw up the system in the process.
@StealthBlade:
Yeah, we know mods don't help those on PC, he was just offering a tip for those who are.
Like you, I'm not sure what Bethesda could do either, and I honestly don't expect them to do anything about it at all as any fix would require at least a partial, if not total, rewrite of the magic system.