[TheDemon]

I think taking first choice from the vets would be fine, as long as they don't get stuck with last choice either. Probably the most balanced is alternating choice, but noobs get first pick. If the ordered list method is too clunky, you could pick team captains and let them call nations. Obviously this would be according to whatever private discussions among the team, but the point is to have only one really active person calling picks so they go quickly.

On cap-specific terrain modifiers, that isn't going to work, I don't think you can mod the terrain of a cap in a way that affects its gold or resources. If you really wanted you could mod the provs surrounding the cap to have a higher population. I'm not too sure on the details. Higher pop will mean more gold/resources. Personally I'm not sure a terrain boost is necessary, but I think the vets can play around it as long as they aren't terrain nerfed.