Well, I suppose fun is of course subjective and we've all played some game in our lives we enjoyed that no one else gives a damn about.
Also, sorry I thought it was a /dsg/ meme to not include or be hateful to BB. I understand if you don't have it or haven't played it why you wouldn't include it.
Skill, Skill/blt, faith/blt, faith, str/int, str, quality. Seems about as varied as the rest of the series, especially when most of your builds in each game seem to saddle up in one or two little areas just the same. Just the nature of meta.
Also, replay value in these games is personal preference. I think 2/3 has least replay value, but I have DeS, DaS, and BB installed all the time. I only reinstalled DS3 for the dlc.
DeS has some interesting lore theories though, whereas the fact that 3 ignores 2 means that unlike 2 which builds on 1 (albeit in a copout and shitty manner) 3 can't really be said to be coherent with the whole series, and 3's story is pretty shit so far outside of the DLC.
1's was nice but there's no need or reason to continue its story.
1 was the story of you figuring out what happened. The party went down long before you arrived, and you put together the pieces as you either fall into the trap or subvert the trap of taking on the flame.
2 was adding to it by using a nearly nihilistic move, that was corrected and routed somewhere mildly interesting but more linear akin to DeS and BB in the DLC.
3 is more open, but I think it's because it is the end. Let you interpret the end however it pleases you. I still haven't heard a lore layout that made fucking sense to me.