One option I've considered doing is making the various sub-skills in Survival perks, not separate skills.
Because of default rules, you can usually just get one Survival skill and just raise it up to improve the defaults of them all. Once you hit 4/level, it's more efficient to up the main skill and let the others default and improve in lockstep.
For a game where the PCs hop regions and you want them to be good at lots of specialties, but pay for the ability, this might work:
Specialties as Perks
When you purchase Survival, pick one specialty as your base area.
Each additional specialty is a 1-point perk, and gives you the skill at the same level as your main, base skill.
And that's it. You've actually learned the skill, you know the equipment used in your TL for that area, etc. - but it's all of 1 point to match skills.
I haven't tried this in play, but I also play with players who generally sink 1 point into Survival and don't improve it, so for them 1 point in one of those skills is equal to their base skill level - they're all at the 1 point level anyway. This rule might cause a problem in some games but it's likely to work out fine in, say, a gate-hopping Dungeon Fantasy game.