I
much prefer using Wrye Flash (a port of Wrye Bash) for installation, as I'm so used to BAIN now, and prefer that infinitely to OBMM. Yes, I know FOMM is somewhat better than OBMM, but still, installing
and uninstalling via Wrye [B/Fl]ash is just flat out superior. IME, anyway.
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As noted above, DarnUI is a must (like DarN, or DarkUId DarN, for Oblivion, of course).
If you want something a little more "hardcoe" than FWE (which, don't get me wrong, is very good) you might like ART (Arwen's Realism Tweaks; there's a RelZ thread on the first page here) - it's compatible with MMM and a number of other key mods. Worth a look, at least, IMO.
CASM is another must. As is something to get NPCs to S T F U about your character even
looking at items they own (or at locked doors/whatever), or simply knocking things over. Gah, that was annoying. :flamethrower:
I like DC Interiors, and similar mods, though some of them are a bit dodgy, so could do with some editing/cleaning/patching. Definitely worthwhile, even so. And at least one or two are basically fine, as is.
I also like Fellout, or Dynamic Weather. Either can be used with Enhanced Weather (rain, snow and the like), IIRC. But using them (FO and DW) together mightn't be so wise.
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Groovatron's great for screenshots, if you're into that.
I don't mind the eXcalibr stuff either, or some of it, anyhow. Adds lots of guns, etc. A bit of fun, but - depending on your setup - could be tricky/inappopriate, alongside other mods.
There are body mods, a la Oblivion. And clothing/armour follows alnog similar lines, you could say. Likewise, weapons.
...
I don't know - what are you after, other than textures and possibly something FCOM-like?