I would agree on using EE armor at later levels. Whether or not you decide you need a 40/45 is up to you, i use a 35 with 120ee and have no issues reaching 55. I have more issues with level 65 upwards.
I find around 25-30 is when i want to start using EE armour over strength, which from the way you've set up, looks to be what you're doing (or in my case dex for daggers and 50/50 for paladin axes)
my personal view is to hit 75 vita, this gives a solid amount of life and hitting a multiple of 25 gives +1 health regen which is better than nothing. Rest of points into strength.
In terms of abilities, try 3 points into knockdown after getting ~3 points into bottomsmash. 27 is high enough to be usable every now and again. I dislike bottomsmash but with fighter it's the best of a bad bunch.
Might be worth trying a barb as barbs get knockdown and retribution also. With the speed you should be doing 1-35 for a barb i'd suggest hitting 60 with knockdown, then 3 points into powerstrike (should take you to ~lvl 35) then a few points retribrution when it stats actually building up.
I prefer the barb ability setup, but being honest i've not played around too much with fighter, which others usually recommend, so i'm probably wrong. Or perhaps it's simply preference.
saying all this, i use mage on first climb as i find using shrines and being able to heal myself against level 1 mobs at level 65 to be slightly broken. (using /whistle 1).
The abilities should fix themselves for samurai, just get his two abilties and 3 points into powerstrike if you fancy it. For paladin things are also complicated as you have multistrike available as well as barb/fighter abilities, his own ability again only really being particularly useful at ~25+ when you actually start taking multiple hits ^^
Why are you not climbing as samuai? can't see any reason why fighter > samurai. Also the bonus stats from failing multiple MQs can start stacking up if you get "unlucky" and more GPs if you pass.
Lastly, if you can get some form of hybrid charm or hybrid character, you can potentially use scales/leather for higher magic defense and use the /whistle 1 technique to heal using the extra mana. Certainly highly plausable on paladin who starts with good int for a heavy class. Not gone into too much testing of my own on this but seems plausable on paladins especially.
Will let you know how my solo monk climb goes, i'm expecting "not well" but we shall see
