Why make things harder? IP cost at low levels would be a big problem by adding ME/EE requirement. Trimmers have engineering skills requirements, so we really do need to burn IP in trade skills at lower levels, but that comes a little later. And at low levels engineer still need to spend IP to use pistols or grenade launchers.

Someday when a emulator becomes reality it may be fun to change some requirement for professions - because it makes sense to require engineering skills to build, operate and maintain a robotic pet. And changing engineer requirements would necessitate a change in IP for bureaucrats and how they create and maintain robotic pets.

The one thing you can do - from a role play scenario - is impose certain rulesets on your game characters. No outside buffs, or no credit or item transfers between characters, or force your engineer to spend IP on ME/EE. I’ve done variations on those themes, and it can be fun, challenging and personally rewarding.