Yes I know there is Flan's plane's and vehicles mods but they both suffer from serious client/host sync issues that imo makes them unplayable that and they are not compatible with IC2's energy system.
I was thinking a few simple vehicles like motorcycle / buggy / plane / speedboat / mini sub
Let them operate off the already ingame Fuel cans and or energy / lap crystals
Maybe a special purpose inventory slot that changes function depending on the tool / item placed in the slot a few ideas
Luminator : headlights :O <- doubt this is possible due to non dynamic lights but i can dream
OD / OV scanner : ability to scan while in vehicle
Mining laser : pew pew
Chest : independent cargo area
I like to load up on equip and just go out into ye wilderlands and find a random spot and mine it out while pew pewing any near by creatures. The suck part is running all that distance and it sucks even more when I find a tonne of ore and can't carry it all so then you have to make 2 trips 