I like your layout. That's almost exactly how I plan to integrate tiers/variations of creatures. Incidentally, it's a bit of a ways off writing, but the advancement system will have some nifty increases in dice size.
Your comment about SPEED - it's a good observation. Of the various stats in that spreadsheet/equation, that's the one that was a "guess" -- the others directly translate to damage output and survival time against standard enemies, but movement is much trickier to calculate.
Here was my reasoning (though I'm open to be persuaded otherwise) -- take a nasty critter like the t-rex. While it's "over there" you can shoot at it, and it can't touch you. It's effectively a giant paperweight. It's speed is important in determining how long you get to shoot at it until it's next to you; and when it's next to you, all that damage output stuff starts in. So for a melee critter, speed is vital. For a ranged one, it's still important for all the tactical positioning stuff but not quite as important. The formula doesn't take that into account at present, though.
I will likely take another pass at the formula once the combat tricks are in. At that point, though, I fear the variations will be great enough that a formula won't really work. We might have to resort to more 'art' than 'science'.
You also mention SPEED as a derived stat. Yep, I think I agree with you. At present, speeds vary a lot. I'll consider a variety of approaches (base speeds for each race, like in D&D/PF; or other alternatives), but yes, duly noted. That is on my list of things to look at.
A couple of things in your stat block
- Jump distances should be in squares, too. I can't remember if I've done that yet in the playtest doc, but in my own stuff I'm recording both because having that there as an instant reference "he can jump 2 squares across automatically" speeds things up. I *love* the way having that info and not making people roll for easier jumps makes them climb and move so much more.
- You have "melee weapons" as a skill. Those should be specific weapons.
What you could do is try the following, since you'll see it in the next packet, though it might get refined a little before then:
- Design your basic critter. This is a career-less critter. Some species or cultural skills, maybe, but no career skills.
- Then apply careers to them (either existing careers or those you have designed yourself). Advanced versions of the critter, then, are simply further along that career grade.
- So you'd need to design a basic Torm. And then a Torm Marine career (unless you want to use the existing Star Marine career). You can then apply careers to your Torm, and even create Torm Medics or what-have-you by just slapping a career onto a basic Torm.
