Hi,
I don't personally think it's helpful to get hung up on terms & theories like 'respect' and 'alpha' etc. I also don't think you need a round pen or to teach tricks like 'Join Up' are particularly helpful. I go along with SisterMare's principle of making the 'wrong' thing difficult whenever necessary. I would also try to focus more on making the 'right' things easy & Good for the horse too. We all - whatever our species - keep doing what works & quit doing what doesn't.
I would strive to make doing as you ask more positive & at least not a chore, so the horse changes his attitude about doing stuff with you. You could plant a food treat wherever you're leading him to, lead him to a good patch of grass, other horses to talk to, use clicker training, etc.
If/when the horse plants his feet or otherwise does the 'Wrong Thing', whether you have a switch, your end of the rope, a cannon

... whatever, make it uncomfortable(doesn't have to be painful or impossible at all) for the horse & persist *until the horse makes a move to do as you ask*. This last bit is very important because if you don't keep at it & let him 'win', he'll learn that to plant his feet & outpersist you is what Works for him. If you continue to keep the pressure on after he's begun to rethink his approach about resisting you, he will decide that doesn't work. So even more important than making the 'wrong thing' difficult is making the 'right thing' positive; easy and preferably rewarded too.