In game terms, or in real world terms, it's the same answer for me. Strapping bomb collars on people or otherwise compelling their unpaid labor is, plain and simple, slavery. Forcing them to fight for your settlement means you're using them as human (or, I guess, super-mutant) shields. If your character were to do that, then others in the wasteland would be perfectly justified in seeing you as Evil (with the capital "E"). In fact, an heroic character might see it as their duty to overthrow you.
"But I only enslave bad people!" is a weak defense, since keeping slaves and using people as human shields is one of the things that makes the Bad Guys bad guys to begin with. That's how you can tell. It's like arguing that you only murder murderers. That makes you a murderer.
Better still- look at it this way. Your character is captured in their sleep by a group who says you've been harassing them, killing their members, and overall giving them a hard time. Rather than kill you, though, they're just going to strap a bomb collar on you and make you farm- for the rest of your life. You are their slave. (Hmmm. Hey, Bethesda- can I get props if this becomes a mission in an upcoming DLC?)
So- are they the good guys, or the bad guys?
It's a REALLY good rule of thumb that, if you wouldn't want it done to you, it's probably a bad thing to do it to someone else. I think that's the Golden Rule in reverse.
As for economy, it strikes me that Wasteland settlements are run like family farms. Of course you're not paying the settlers, they're forming an extended family unit, with you as father/mother figure. They eat food you provide and live in houses you build, wear clothes you pay for. Do children in a family get paid (other than a token amount) to do chores? It's not communism, it's a family. Communism was a reaction to capitalism; settlements are pre-capitalist, even a subsistence economy.