Hmm, I do like the idea. Though it could be done in a few different ways.
There's the "support drone" approach where you can craft and mod the machine, charge it up and then have it as a combat utility that when activated can be released as a temporary ally while fighting. You could either make it so that it can be broken or you could make it work like shields, where hits drain it's battery power instead of health and when it runs out of power it returns to the character and the utility item deactivates.
You could do a similar thing except make them a one time use item. Or make it so that they last until they're destroyed, and then you need to craft or buy a new one.
It could also be specialised as 'combat drone', 'medic drone', 'stealth-drone', etc.
Another option is to have the drone as a scouting drone. Essentially give it a flat stealth skill based on the crafter's mechanics and allow the character to use the drone to scout stealthed instead of the character. Naturally this wouldn't be as good as stealth since you couldn't interact with things but it would still be useful for scouting and maybe watching round a corner for your character. Would be even better if it could remain undetected when the character is discovered. That way it can still scout round corners so that the player can be ready for enemies before they show themselves. This might even be an effective solution to the instant one-shot kills I kept suffering at the hands of surprise snipers and whatnot. Though to be fair I did make Endurance one of many dump stats that build, haha.
While i like your idea of a robo arena, I would still prefer just more normal arena fights and gauntlet runs. was a little disappointed they weren't as replayable as the npcs suggested.
