No, I didn't play Demon's first, I'm still yet to beat my first playthrough shamefully. But I have been putting more time into it lately.
I didn't put any real restrictions on my first playthrough in the sense of solo'ing every area and boss. I just played the game how it was presented to me, if I had humanity, I would try and stay in Human Form. If I saw signs, I would summon them, they failed a lot before the patch, but every so often people would get in my game. I got killed by twinked out invaders and shrugged it off. I would cheese bosses if I saw an opportunity, I was just getting through the game however I saw fit. I didn't wiki for areas or huge tips, but I would look up something or ask a friend what they thought after I had come across something I couldn't figure out.
I will probably try to play the next Souls game more "blind" than I played Dark Souls, but I'm probably not going to avoid summoning people or ignore the online aspect first time through. The online in Souls games is the main reason I keep playing them, it's so unique and fun. I will make sure to avoid summoning twinks for first playthrough, and since I will be playing day one, I probably won't run into too many.
I see...
Completely agreed that the online feature is so amazingly integrated into the game despite the lag and what not. There are something in that design which is brilliant.
I often read people complaining about the absence of voice chat which makes me smile. IMO it's not a restriction but by design and not integrating it was a good decision.
As for me, I came to Dark Souls after having beaten Demon's Souls at least a dozen of times through the 3 versions if not more. So I was prepared and at the same time that made me do some mistakes given there are some tiny differences in the design that can have big incidences in the game. So, coming into Dark Souls completely new isn't really a disadvantage since you start fresh and not influenced by the previous game.
Anyway, I played my 1st playthrough hollow for the most part. This was one of the bad reflexes from Demon's because in that game you loose a part of your HP in soul form, so seeing I don't loose that in Dark made me go hollw, no mention that in Demon's being in human form altered the world tendency, which doesn't exist in Dark.
Being hollow, helping people to practice the levels and bosses was my way to go into Dark Souls. I beat all the bosses solo except for Gaping Dragon (what the hell) and so, I missed the invasions (including the NPC ones).
It's only starting from NG+ that I began loosing my Demon's Souls habits and started to play the game differently.
Last year I did a SL1 run in Demon's Souls and I still have that character, so I can now level up in NG+ and help you if you need. The online aspect in that game is much more solid since it's server based.
I have the 3 versions of the game, so don't hesitate to ask and I will gladly help.