[dirtywick]

It's pretty dependant on the nation, but here's a few things I always consider when designing a pretender:

The pretender is most likely going to be your most powerful unit for a really long time (unless it's sleeping, even then...), so what use do I want for it?

For magic, do I want it to take provinces and use buff spells, give me access to magic/spells/items I would have a lot of difficulty getting otherwise, a huge early research lead, finding a lot of magic sites, get a good bless for my sacred troops at the expense of a possibly powerful or diverse unit, or some combination?

What kind of scales will compliment my nations troops, or more specifically the troops I'll actually be using? Gold expensive troops benefit from order and growth mostly. Resource needs production. The opposite is also true. If I plan on using a lot of magic items/summons, Luck can give gems as random events as well as gold; some nations benefit from a variety of gem types and will benefit from this more than others who have few paths. Mages with old age benefit from Growth, but if your nation has no old troops Death can be an option. Turmoil causes more random events, and with high luck you'll likely get a lot of positive random events. Magic gives research/penetration bonus, Drain a research penalty and more MR to your units. There's ways around both for some nations, like research bonus items or spells/items to boost MR.

Then I look at what I want, and what kind of "state" I guess I want the pretender in. For instance, a strong bless allows you to expand quickly with sacred troops, so choosing an awake pretender isn't as helpful and will free up points for better use. However, a pretender designed to research/site search benefits from starting early and getting the gems/research done earlier, so having them asleep hampers you for a lot of turns. Additionally, a pretender designed for combat should be awake and put to use as early as possible.

You also have to consider the map size and number of opponents as well; a small map will take a much shorter time, so scales like Growth that grow stronger over time or Luck that benefits from more provinces won't have as big an impact as a larger map, or a pretender that's asleep might never awaken before the game is over. The opposite is also true.

Then you have to find an efficient balance between them, using as many points as you can. You won't be able to get a strong pretender chassis, lots of magic and a good bless, and good scales, and have it awake.

I guess the main thing is to take a look at the nation you're playing, figure out their strengths/weaknesses and play them a bit, then you'll have a lot better idea of what kind of pretender will work for them.

Man, might have more questions now than answers. One thing I'll say for certain is Earth is usually a fair choice for a pretender. Blessing gives sacreds reinvigoration which is never a bad idea, and additional prot on the pretender itself, as well as access to some nice buff spells and hammers.