Can I add fins or something to the pipes to help generate more heat?

Not usually. How old is the heater? Newer units have more fins to be more efficient but don't know if the replacement cost is worth it. Perhaps a $20 ceramic space heater would be a good choice for a heat boost.

Was not thinking about replacing the pipes but adding something like more fins,or something that attaches to the pipes to add more heat. Not sure how old the system is but its old.