Minor Electric is a pretty big disadvantage, I think this is all the types immune to it:
Data Center
Troop Accelerator
Core Shield Generators
Counter Spy
Planetary Cloaker
Attrition Emitter
AI Eye
Warheads (including NRC-launched ones)
Fabricators (doesn't matter for your ships, does for the AI)
Several Golems
Autobombs
Alarm Post (normal and special forces)
Raid Engine
All Turrets (pretty big difference for the AI)
ZPG
Zenith Space Time Manipulator
Radar Jammers
Planetary Armor Booster
Planetary Armor Inhibitor
Interplanetary Munitions Booster
Black Hole Machine
Zenith Reserves
Distribution Nodes
Super Terminal
Co-Processor
Nanoswarms (heh)
Regeneration Chambers
Energy Reactors
Harvesters
Manufactories
Science Ships
Core CPA Guard Posts
Core Raid Engine Posts
Space Dock (and similar)
Advanced Factory
Engineers (and similar)
MRS
Colony Ship
Transports
Self Destruction Guardians
Warp Gates
Anyway, yea, Raiders should have a lower cap-cost than Teleport Raiders, that's just an oversight on my part. As for damage and durability... For a while I tried to balance it so that cloaking and teleporting stuff just got 20-40% less than the normal counterparts, but that tended to make them look useless to folks.
The bonuses are a bit different but somewhat favors Teleport Raiders: heavy, structural, polycrystal and ultra-light is generally a more useful set than Heavy, UltraHeavy, Artillery, and Swarmer. But not always. Structural is so key because of forcefields, and probably you aren't zerging full caps of teleport raiders into forcefields as part of a "raid", though I suppose it could be effective. UltraHeavy can be helpful for Raiders, I imagine. And in fleet combat having bonuses against Artillery and Swarmer covers a fairly large number of types.