The way I try to do make sound like the bass guitar is trilling my notes.
For instance, if a song is in E, & the main pattern is 1-6-4-5,
I would do it something like this (ok, this is just from memory, excuse any errors) ^= trill, trill means that you hit a note a half step or a whole step behind the one you're landing on for a split second:
1: ^C#,^E
6: B,C,C#
4: ^A
5: A#,^B
1: C#,F,E
6: ^C#
4: ^A
5: C,B
1: ^C#
6: D,^C#
4: C
5: ^B
etc
So all we are doing is looping using any fill ins that fit.
for slow songs I find that just playing those key points makes the song sound really good eg:
1: E (sustain until the 6 comes)
6: ^C#
4: A or C
5: B
1: E or C
6:C#
etc
I don't know if that's what you were asking for. But I find that trills add an extra "boom!"