Just forget about the whole speedsoft thing. Playing indoors is just casual airsofting, speedsoft doesn't really have a meaning other than shooting a lot with a negative connotation.
You can play indoors and be extremely effictive with just a gun, goggles, chest rig, and dump pouch.
Guardians of Asgaard - KF32
VFC H&K 416C
VFC KAC SR16 JL Billet SBR
TM FN Five-seveN