I don't use Reaper, but I do use the Cockos plugin pack that includes the ReaEQ, ReaComp etc. Those are my default channel plugins. Even when I was experimenting with Reaper I didn't use the JS stuff much.
The system I usually use is a medium format mixer connected to a line level interface, so technically I am using a preamp ahead of the interface because it's required. There's also a patch bay and rack of hardware compressors. Most of the time I'm working on familiar performers so it's pretty safe to commit to a bit of processing on the way into the DAW. If I had to I could easily depend entirely on plugins.