Hello, I am a noob myself, but my experience shows that:
I ignore almost all of the side quest(except tutorials and couple at the very start) and yet most of my characters have finished silver around 50 - too much XP for killing mobs, on gold the pace is much slower - I am finishing it around 60, so, yeah, side quests is mostly for platinum/niob difficulties
There is a special cheat for this - weapons with the stat "+%% life leech"(dont confuse with +X LL, it should looks like "+1.2% life leech", not "+12 life leech" and not all weapons have this stat - only two handed, throwing stars, knuckles,...But I see it like OP - if you have proficiency with the weapon and tactical lore skills - you should not have problems with other weapons, I killed bossed even with resistance to my weapon damage type - just it takes some time and patience, but at least it gives you the feeling that its a boss("have you played old school scroll actions games where bosses were like - oh, FECAL MATTER! I have reached him with only 1 life left and he one-shot me:)") - while %%LL weapons kills bosses like common thrash in a couple of the seconds
Bargain skill, hands down. Just keep it up to your level. But I hate it - so you could use Enhanced Perception instead like me, even if your weapon bad you will get many armor pieces with slots and slots can be enhanced with blacksmith by choosing whet(+damage, +attack). Or... you can download stashes with a plethora of items on this site and loose interest for this game
I also advice to ask about your character build in the corresponding sections, something is wrong with your char - my Shadow Warrior had no such problems, even though he has no bargain or EP skills, items in stash or such....(I must confess - he has a blasck smith skill it helps a bit, actually)
Good luck on your exploration!
Offtopic question to admins : whats the heck is " FECAL MATTER!"?