I also played way back 2010 to 2012 and I just returned playing the game 2nd week of December 2016. I will try to answer all your questions since I'm currently making an STR, 1 handed magnus that is currently struggling to 105.
Forum signature: It is auto generated on how many post in this forum. Yeah, yours is better than mine.
This is the summary of Pros and Cons for me:
Paladin - Higher Block rate
- No 105 aoe skill: Shield Punch
- Lower level of unique buffs (auras) if it came from Rune Knight
Magnus - Lower Block Rate
- Higher PDef
- Dual Sonic Blasts (Ranged)
- Higher level on unique buffs (auras)
*Yes, the skills are all fixed and you can't use axe anymore if you're going for sword. Sword is better for Sonic Boom and Dual Sonic Blast
*Yes, 2 handed Magnus is also good if you want more PATK but less pdef and quick casting skills. but if you're planning to go dual-wield, better to go SM instead for higher level of expertise
*I'm not a fan of DEX. I will go pure STR with STR items and strike accesories and will go PURE VIT with STR items around 135+. Note: Rune Impact Nevermisses and Dual strike's poison effect is still applied even though you hit it as a miss.
*Comparing to 2-handed Magnus and 2-handed destroyers, it is like you will have to choose whether you want a lower PATK but higher PDEF or higher PATK and lower PDEF. I'm not a fan of destroyer since you will not get my favorite skill: Rune Impact. It's up to you what will you choose but every character has it's own strengths and weaknesses.
*If you're going to ask me, I think the game will be much better without donation items - but I think it is inevitable since the game also needs $$$ for the game maintenance and improvement.
I hope I did helped to answer your questions.