So I restarted the game since I was not satisfied with my characters This thanks to very little info to work on, but also due to how stat increases work.
Stats don't go up randomly, but are heavily biased towards the "prime requisites" for the class. So a Priest will always, or nearly always, gain a point in PIE when leveling up, and ditto for Mages and Int, while a Thief can level up to level 10 without increasing STR or INT one bit, thereby taking forever to qualify for Ninja, for example.
So to plan for promotions you kind of need to boost the stats you need for promotions, and not those that are most useful for you current class.
I also found out the stats required for the Philospher (advanced Mage) and Mendicn (advance Priest): INT/PIE 15, VIT 12, 10 DEX and 12 MAG DEF. I think the Monarch also needs Magic Defence (and a Good alignment).
With 19 bonus points you can start with a Mirelli Mendicn, which really speeds things up.
A Wallback should also be able to be able to start as a Philosopher, but max 16 Speed is a huge turn off. I'd much rather have a Tairon with 20 Speed, but a Tairon would need 22 bonus points which is not realistic, but he should be able to change class at lvl 3 with optimal stat allocation and no bad luck.
My "dream team" for a diverse (all races included) party is:
Sadeeq Knight
Tairon Ninja
Human Samurai or Bard
Wallback Swordsman . Preferably in the rear equipped with a poleaxe. Hard to keep alive in the front.
Mirelli Mendicen
Tairon Philosopher
Bard becomes kind of situational, though. Highly useful in anti-magic zones.
But only a Samurai can wield the fabled Muramasa blade, apparantly.
With Knight, Ninja and Samurai you have a very solid front line.