Any recommendations on good bass amplifier plug-ins which go beyond the basic (sorry) one included with Logic?
I'm a big fan of Izotope Trash. The speaker models are great, and there is a lot of flexibility with their preamps, filters and multi-band dynamics. I use it on bass, drums, guitars, pretty much anything... And the price is quite reasonable.
I've found that using N.I Guitar Rig's small selection of bass guitar amp settings very little to be desired.