Hey ElOrso,
Welcome to the forum. I'm glad to hear you are enjoying Frostgrave!
I think the idea of a 'ogre' soldier is pretty cool, but I think it is perhaps a bit powerful. The problem isn't so much the cost, or even the stats, it is the potential those stats have. With a few spells, or a magical item, he could become very powerful. At minimum, I would say that the ogre shouldn't be allowed to carry an additional items.
That said, taking up two soldier slots is a big price to pay and many people would probably rather have a knight, a marksman, and 100gc, so maybe it isn't overpowered. Sounds like it needs play-testing!
My advice for your campaign, use the ogre against the opponent that doesn't mind, when playing against the opponent that does, replace him with two other soldiers (ogres often get drunk at inappropriate times and miss battles)...