player base is for sure much smaller than let's say on PS3, so you have to be more careful when, where and @ what sl you try to PVP. for me invading works way better than being summoned/summoning, no issues with GFWL here.... but i'm not using DSCFIX
try following things:
- play on weekends and check the steam page of dark souls, it has a counter how many people are "In-Game". I'm pretty sure this is just for the steam version, but it gives you some idea how active online is atm, 2000-3000 are good numbers
- for random invasions as darkwraith: try sl50 @ lord areas, sl35-40 in anor londo, catacombs, sen's
- sl 100-120: no random invasions, unless you are very patient: go to the PVP spots and host (forest, burg, township,..) also try the rss/eye of death there
- based on my experience township is the most active PVP spot for duels on PC
- know the restrictions each covenants has: forest hunters can't invade downward without any limit; for darkmoons a higher sl is better; dragon eye PVP is generally hard to get...