I've played Olbivion for years, both modded & unmodded, but never got around to playing SI. Are there any recommended stable mods for Shivering Isles that will enhance the experience, or make the game a little more challenging? I actually don't want to install too many mods to avoid bloat & possible conflict, perhaps just a small handfull of the best. Something that fixes level scaling maybe and doesn't change game mechanics/storyline too much. TIA.

There isn't much. Take a look at this 'http://www.gamesas.com/topic/1113355-any-good-shivering-isles-mods' thread.

-Dubious-

Since I've just played through with ZuThe Skunks Overhaul, I would recommend that. However, read the documentation, I doubt if a low-level character will survive, especcially if you meet one of the Hunger range without a sackful of cure paralysis potions.

jcjcjc

I could vouch for http://oblivion.nexusmods.com/mods/34245 overhaul as well. However, some things are out of whack, the hungers in particular as said. Unless you use Mehrune's razor or something similar on them, you'll have little chances of defeating them. Some of the boss battles as well are an insane grind or outright impossible unless you know how to beat impossible odds (I don't), which is the idea behind their redesign, but to me it detracts a bit from the fun.

Another issue I have with it is the use of scripted changes to actors, particularly disposition. After certain points in the MQ with it, you'll find that persuasion or personality has even less use in the isles than in vanilla, everyone's disposition to you is pretty much fixed.

Also, unfortunately it has its fair share of bugs. Most are harmless enough, but better not to do the Vitharn quest with it installed, since it will likely halt scripts while you do it.