BoNam'oLafs
I actually calculated everyones averages for all classes. (Too much free time . . .

Just basic averages though.)
Some surprising and some not very surprising results.
On the subject of Roshe: Swordmaster doesn't make him any better. He doesn't get any more strength than Freyr/Kain/Abel. And on top of that he loses 7 speed and 11 luck. (Same about everything else. Oh, and the speed advantage is actually much bigger because the other Paladins average up to 40(!) speed as Swordmasters. The Swordmaster's speed cap makes the difference look smaller.)
So unless you really need a Swordmaster that's slow, easy to hit and takes a lot of damage (9,6 Def) . . .
Barts trained as a Fighter before promotion and axe using Hero after overshadows Oguma in every way.
But literally anyone is good as a Hero anyway (even Daros). But just looking at the growths I wouldn't have guessed that I really should try Roger the Hero. Roger? Isn't that the Knight that was missing in FE3? How about maxed strength and speed, almost maxed luck +50HP?
Some combinations to try:
Freyr the everything (The choice is up to you.)
Doga the Berserker (No Def available.)
Maji the Socerer (Don't expect >15 Mag though.)
Tomth the everything
Katua the everything (Most overpowered unit. Let's take Swordmaster as an example: 54.8HP, 23.2Str, 29*Skl, 30*Spd, 21.4Lck, 16.2Def)