I have a 1" baffle to fit my speakers and they BARELY fit! If they were any deeper they'd hit the window, and more on the baffle and the door card wouldnt fit back on lol. I have Rockford T162S front and rear and amped up and they sound good, but I really need a sub.
VAG speakers tend to sound pretty good if you just amp the standard ones so maybe try that? TBH, changing speakers is a pretty subjective thing. Get to an audio
shop and listen to them for yourself then you can decide what you like best. Also sound deadening is supposed to really improve the bass from the door speakers. Costs soon mount up tho!