Name's quite a handful, eh!
Overall impressions? A huge step down. I mean, I knew that Devil Summoner 2 was considered a HUGELY improved sequel, but I didn't know what to expect. You only take one demon at a time, melee combat is reduced to a single button(No more weak/strong blows), no demon negotiations(Do you even SMT?) and Raidou feels very slow.
Regardless, the thing I like the most about Devil Summoner is the setting, the characters, the lore. I love the idea behind the four great Devil Summoners and how they are succeeded by people taking their names as titles, that's very cool. I love the setting of a Japan early in its westernizing, and how the Devil Summoners fit in this world. I love Raidou's cast, Tae the reporter, Gouto his mentor/first Raidou, and Narumi his chief/partner. I also took a liking to Nagi, but she was introduced in the second one, so that's one character who I won't be seeing again... this time.
The new villains look very interesting. I kinda like the human enemies from the second one better, but this robot soldier-army is very interesting, and I love how they kick Raidou's butt in the beginning. Speaking of Raidou, I love how you take control of him as he takes the test to become Raidou, the strongest in the Kuzunoha family... yet the test has him battling low level demons! Guess their standards are reaaaally low, heh.