Here's my list, number in front of them is my rating from best to okay.
4. TMO Realism and graphics quick death for swabbies
https://www.subsim.com/radioroom/sho...d.php?t=250635
3. TMOwTW Realism graphics and better chance of survival
https://www.subsim.com/radioroom/dow...o=file&id=4801
1. Darkwaters German perspective Realism and great graphics
https://www.subsim.com/radioroom/sho...ght=darkwaters
2. FOTRS Realism and graphics
https://www.subsim.com/radioroom/sho...d.php?t=243064
5. Japanese Mod Vanilla graphics, Japanese subs perspective
https://www.subsim.com/radioroom/sho...d.php?t=137761
6. We dive at Dawn British sub perspective vanilla
https://www.subsim.com/radioroom/sho...d.php?t=170639