Sir Müllich only adds 3 to speed; what's the point of him on large maps, where the opponent will pump up their specialization and be able to move their units around even faster than Müllich?

But wait: 1) +2 to speed 2) What does hero specialization add to unit speed? AFAIK only attack and defense.
For example, Hero Fafner from the Tower (Naga specialization):Fafner increases the Attack and Defense skills of any Nagas or Naga Queens he commands for each level he attains after the 6th level.
I'm not strong in English, but I think this means: Fafner increases the attack and defense of all Nagas and Naga Queens he commands for every level after the 6th.
Is anything mentioned about speed? Maybe I missed it. And as much as I've played, I haven't noticed such a thing!

And besides, any hero's specialization only applies to one specific Unit, whereas Müllich's applies to all.