Futaleufu I've enjoyed every game in the series. I absolutely loved the first and thought the second was pretty great, too. I really did prefer the time constraints in those two games and it got me to play through and essentially master the first game. The third and fourth change things up, so that did make fans grumpy (like me), but after digging in I thought they were equally fun in their own way, even if they did get away from what I enjoyed about the original two. The biggest change to me is the lack of timer but also the reliance (and ease) of using the combo weapons. I seem to recall using them constantly in 3 but I know for sure in 4 I essentially never was using anything but combo weapons. But yeah, if you like 3 you'll probably enjoy 4.
I completed Torchlight II, so one Blitz game complete. My fun started at around a 7 and had a steady decline to around 3 or 4 by the end. I seem to recall that matched my feelings for the first game and honestly many games in the genre. Once you start your build you feel locked in, which then also can limit gear you want to equip. Difficulty ramps up a ton by the end so it was mostly just run forward, pop every skill cooldown, clear a section and die, restart the floor, and repeat until I make it off that floor and do it all over again.
Also, just realized that while I added all Shovel Knight DLC as one slot on the Blitz I did so thinking there were two. Completely forgot they released the third, and final, campaign. So now I have all three of those to get through. Oops!