I have been waiting for a series of dedicated color reprints of classic Peter Parker, the Spectacular Spider-man for years - so, the forthcoming MMW will be much appreciated! It's been a long time in coming, but better late than never.
The iconic cover to PPTSSM #1 was incredible - the Tarantula was a great villain, and I really enjoyed the storyline as well. It will be great to have these early issues in color, since I've only read them via the b&w Essential (back in the 200X's).
IIRC, PPTSSM was initially supposed to focus more on Peter Parker's personal life (hence, the title), whereas ASM was supposed to have more action. Not sure if this was actually the case, however. I will say that in the '70's, PPTSSM seemed to be more of a stand-alone title in that you didn't necessarily have to read ASM at the same time; but, chances were if you read/collected one title you would almost certainly read/collect the other (and there were references to the other title in each series). By having both titles focus on Spider-man, it was a great way to give the character more exposure, and also made Marvel more $ as a result (LOL). Then, of course, you had Marvel Team-up - which also focused on Spider-man....
By the '80's I remember both ASM & PPTSSM being fairly interchangeable - and having a lot more cross-overs by that time; notably the Doctor Octopus/Owl gang-war storyline. Though, there were a lot of notable stand-alone PPTSSM issues in the '80's - notably the Cloak & Dagger origin issue; the issue focusing on the Toyman; another cool issue with Stilt-man which had a great cover (in which he was destroying the cover logo - LOL); etc.