I dont carry that much, spell scrolls weigh almost nothing, I have a bow, a sword, and a silver dagger (sword for combat, bow for shooting cliff racers, and a silver dagger if a scamp or something gets too close) plus arrows, and heavy armor/shield, clothes and a magic ring, and lock picks and probes. Its just that when out on a quest or just exploring i tend to find valuable and heavy items and no one to sell them too immediately so I end up carrying them
I still haven't found anyone to sell a Bittersweet Cup (sp?) to.
as for armor suggestions, i go for Ebony and Orcish (mainly because ebony is so hard to find) but thats heavy.
keep the bittercup, it could come in handy to you later if you join the theives guild and achieve a high rank