your chain order looks pretty good to me. as you may soon learn on here, there is often no right or wrong way to do things, it's a matter of painstaking experimentation
i hear your complaint about the sansamp's distortion. are you using an active or a passive bass? i use an active, set flat as per the manual. at times i have found decent settings, other times it sucks. it also seems to depend on volume, i remember one gig i really digged a nice overdriven tone i had happening..now..can't seem to get it back at practise.
for the record..the sansamp while not give you distortion, it'll be overdrive :P what's the difference? well... hehe