Welcome to the dark side! One other option is Multi-SH4, which makes it easy to run multiple installs and do your own side-by-side comparison.
I've only played RFB, mainly because the talk about the evil DDs and planes in TMO scared me. I won't be playing either for awhile because I have this obsessive-compulsive anal-retentive need to play in a linear fashion, and I have three u-boat careers going in 1939 at the moment, and 1942 is a long way off.
I'm glad you don't feel the need for the harbor traffic stuff. I consider it a hangup for me, not a good thing. That said, the harbors I've seen playing RFB look pretty good compared to stock, and they may actually be due to RSRDC, which means they'll show up in both supermods. I don't know about that for sure, but I do know SH4 is much better than a lot of people give it credit for, especially with the work that's been done so far.
