[Endoperez]

The independent enemies are just called independents.

Luck scale provides random gems and mages (generic mages and heroes) in addition to gold and the occasional resource site, as well as protecting from population death and barbarian raids. For just gold, Order scale is better, both in the very early and the very late game. The reason for this is that you need to conquer some area before you can get the maximum amount of events available per turn (3), and that you can't get more than those.

Personally, I find that Luck is much more fun, so I prefer it over Order.

If you haven't updated to 3.10 yet, I suggest doing that. Hydras got a big change in that one, getting several forms, losing heads, etc. The first form will have just few hp, but don't care about that. Think of that as the amount of hp ONE of the heads has. That said, hydras are a bit hard to use. You could combine them with undead to finish off hard-to-hit enemy units, like sacred cavalry.

Death magic: Enchantment gets you ground troops (Reanimation is quite costly unless you get better types of undead, e.g by playing one of the giant nations, but Raise Dead/Skeletons is already quite good. Enough mages casting that can conquer provinces on their own. Pale Riders is the next big spell on Enchantment), Conjuration elites and tough commanders that you can equip for battle (Black Servants, Bane Lords and Wraith Lords are commanders).

If you go for Enchantment, Gift of Health would be really nice. If you don't want to take pretender for it, try to forge booster items. Page 282 of the manual lists the boosters. Even with them, unless you get a hero you might have to empower one of your mages, so if you don't know what else to do with a pretender take good scales, supportive bless and enough Nature to cast Gift of Health. Taking an imprisoned pretender won't hurt if you don't need him for the early game, so you can probably afford something suitable. Just remember to compare how much the magic and dominion you want cost with different forms - increasing a path gets expensive very fast unless your pretender starts with that magic.