Mag block- big enough to use, useful enough to carry.

LMF and BSA Hotspark type ferro rods- handles make it easy to use, good for thousands of fires but still compact, light weight, and nearly idiot proof.

Sparklight and similiar one handed spark wheels- Compact, good for hundreds of fires, and you can use it one handed.

Thermite- because some times you REALLY need a fire and no questions, not even from that menacing thing from another world who is drooling in the corner.

BTW, welcome to the fire new guy.