So I've been reading the forums a bit and from what I read I hear anyway you build your character if you know what to do the game is way too easy.

I have a lvl 30 character that has mostly focused on smithing (86) and light armor+one handed weapon along with destruction and restoration (mostly because I just heal heal and heal some more).
I intend to get all the smithing/alchemy/enchantment perks and then whatever is left over will go into destruction/ one handed and light armor.
I just tried joining the companions and went to the dustman's cairn thing. I'm playing on adept and I'm getting slaugthered but not like sort of killed I mean completey mercilessly one shotted
by half the mobs in there. I'm at the end fight and have 7+ mobs trying to kill me and farkor to trip over.

I will be the first to admit I'm not much of a FPS person (read I'm really really bad) never played them, liked RPG's where I could have story + number crunching or overlevelling to help me out, but
I would have not expected to be getting slaughtered quite as much.

Is the problem that the mobs scale with level wheras I don't really? Smithing is nice but probably doesn't quite cut it? My destruction magic seems to not even graze them should I give up on that?

Any suggestions or just enlightenment would be nice.

Youre probably right in that youve concentrated on non-combat skills too early (especially smithing). If I were you I would concentrate on building up combat skills, so that youre not so outmatched. Until then, theres no big shame in turning down the difficulty.

take a break from serious quests, and to level up useful combat skills go wrestle some low mobs like wolves, skeevers, some bears perhaps, Alduin, .... uh wait what?

Turned out I wasn't at the end fight. The end fight was a cakewalk it was the silver blood guys that were a nightmare. Oh well I'm used to playing late blooming characters until then that's why I don't play dead is dead.

Im not brave enough to play DiD!

Does your current equipment reflect your skill in smithing?

I ask because I made the mistake to hold off on upgrading and crafting appropriate equipment until I could create the 'best' equipment, but then I ran into the same problem. At 86 smithing you should have some highly upgraded armor and weapons at this point.