I tend towards liking pretenders with very strong magic in one or two skills rather than having it spread about, but I have tried the jack-of-all-trades type enough to know that approach works OK.
Magic paths give benefits to the mage itself (which includes pretenders) for even 1 point of power in that path. If your pretender is intended to function as a combat unit, I think the accumulated benefits for having many paths nicely offsets the fact your blessings won't be as potent.
The reason I usually take a very high level in one path plus a medium-high level in a second path is because I love the super-spells and do enjoy the second-tier blessing effects you can only get from having a starting power of 9+ in a path. It's a taste thing, though, not an "I'll never win if I don't do it this way!" thing.
I do, however, think that you wouldn't be getting as much out of a diverse pretender if he/she/it wasn't on the front lines, actually using those boosted stats. If you tend to have your pretender hanging about the home province, casting spells, enchanting stuff, and so forth, then I think focus rather then diversification is what pays off more.
I haven't played as a Naga, but Dragons are just too much fun. I haven't played the cost-analysis game to see if they are worth the price compared to others, but their breath attacks, transformations, and the fact their really-strong-in-one-path natures fit my play style means that they are worth it to me.
Re: Nagas and other "lost" pretenders
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