Question:What are the differences between a european-esque knight, a centurion, a samurai and a viking berserker?
Answer:What the player wanted to get out of the game.
In Rolemaster there are two approaches to getting exactly the PC you had in mind. The first is the hard earned cash version where you go out and buy all the Rolemaster companions and build the character to the profession as defined in those books. There will be as many companions for the new RMU as there is demand for and there are more companions for RM2/RMC/RMSS/FRP than any sane person requires (but we are roleplayers so we have them all).
The other approach is the ‘distilled essence’ approach. What makes a viking a viking? Well I would say, a bit of it is equipment, chain shirt, big shield, battle axe and a brace of hand axes would just about do it.
Skills-wise then the must have is Frenzy (bonus ‘to hit’, double damage and can take more damage before falling down), sailing/navigation/rowing and tale telling would just about cover it if you asked me.
You can have all of that with a stock fighter profession with points to spare.
The Samaurai? Well, rigid leather armour, katana, wakizashi (short sword), long bow for both skills and equipment and caligraphy as a skill. There is a useful skill called tumbling attack and a couple of combat skills such as reverse strike to attack people directly behind you and Ia strike to draw and strike in a single movement. I think that just about does it.
The knight is heavy on the weapons and armour, platemail, broadsword, flail, and lance, ride horse and some heraldry skill.
The centurion I would give a platemail breastplate (Armour Type 17 in Rolemaster parlance) and shield, shortsword, pilum (javelin) and definitely some skill in seige engineering and tactics.
Rolemaster has some really useful skills to compliment the straight weapon and armour skills. You do not need them all but you can use them to add that bit of something extra to a fighter. There are tumbling skills for evasion and attacking, reverse strike for attacking those behind you, two different ways of getting a quickdraw (by adreanal move and by Ia strike), ambush, martial arts (several), jousting and subduing to name just a handful.
I have found with some groups of players they start out with a strong sense of identity and a concept behind the character but as soon as you wave a nice magic item in front of them the concept goes out window.
Here is what I mean Player: Thrud is a barbarian from the wilds and shuns heavy armour as a sign of cowardice. 24 hours pass… GM: You open the chest and inside is a suit of +3 platemail Player: Cool I’m having that!
In Rolemaster you generally end up sticking to your original concept more because the choices you make at character design time can have a long term impact. You rank the different weapon skills so that one is easy to learn (cheap to buy with development points) and the others get progressively more expensive. If you have already chosen to learn broadsword, flail and lance then you regardless of how good that battle axe is it is going to be a major investment in time and effort before you get any good a wielding it. The same goes for the armour skills. To become fully proficient in moving in any type of armour takes an investment and commitment. Really light armours are easy to learn but your chain and plate armours will take you many levels to learn.
Going back to professions (character classes) Rolemaster Classic with no expansion of the rules has nine pure spell casters, three hybrid spell casters, three semi spell casters and only four non spell casters (realm of arms as they are called). This is not because Rolemaster is lop sided and bias towards the magical side of fantasy rolepalying it is because you can do so much realise your charcter concept right off the page with no need to define new professions. Those four are actually just Fighter, Rogue, Thief and Warrior Monk but with that spectrum from heavy armour to no armour as the default starting point you can pretty much build whatever you want.
My favourite theif character (may the gods rest his soul) wore platemail, he used a spear, hung out with knights most of the time, he had learned a little mentalism magic (attack avoidance and self healing) and was very adept at adrenal moves. He could hold his own in a joust using a lance, which is treated as a similar weapon to spear so can use half his spear skill. When his skill is combined with adreanal move strength to get a boost to his attack roll and deliver double damage and magical protection from his spells (staking shield and blade turn) he could get pretty far in a tourney. He was even mistaken for a Paladin once and whilst he never claimed that himself he didn’t see the need to set the record straight too vociferously.
Buying Platemail for that character was a nightmare and a real drain on his development points but I wanted the character to be more con artist and confidence trickster at court and for that the armour was worth the investment. Without the amour on he was a competent thief and forger more inclined to steal documents than coin.
A different arms user I built recently was the one I described on Monday that leads with a volley of hand axes, one in each hand and with Adrenal Move Speed. He really does pile in like a ton of bricks. His weakness is that he is as stealthy as a bucket of bolts in a tumble dryer.
In Rolemaster there are so many choices beyond the “long sword, long bow, shield and plate” fighter of my D&D days but you can play that too if that is what you want.