You won't know what you like and don't like about a machine until you have lived with a machine for long enough to understand the rules and such. Given that, I would just go with whatever is currently available for purchase and appeals to you the most. Your first machine doesn't have to be your favourite. Also, you probably won't have much mechanical knowledge about how to fix things going wrong on your machine right away, so just make sure nothing needs fixing immediately.

My point is that we don't know what will be a good long term pin for him either, because we're not him. Enjoyment of a game is subjective. I personally love my three pins, but I've seen hate for all three. I can understand why people appreciate certain games that I am not a big fan of, due to one reason or another, but how can you know what themes and music and artwork someone else will like? He might as well tell us nothing about pinball and more about his other interests haha.

So, Willis, from you pin choice you don't seem to have any interest in music pins. Is that fair? Does the game music and sound effects matter to you?
What about superhero themes?
You've got both kooky themes (MM) and serious (LOTR), so do you not have a preference?
You've got LOTR on there, would you consider any other movie-based themes?
Does artwork matter to you?
The list goes on, and if you want us to truly recommend a game that will last for you, those things are important.

Further on to that, what gameplay aspects do you like and dislike about the games you have played? For example, do you like fast games with orbit shots (that's where the ball swings around and comes shooting back to you)? Interactive toys? Wireform returns that bring the ball back to flippers? Multiple flippers? Upper playfields with more flippers?

Gameplay, theme, music, cost, toys, availability of mods, etc. these are all things that matter.

If you just want us to stick to the 3 you listed, go with LOTR. It's the cheapest, easy to trade or sell if you don't end up liking it long term, has mods available, gameplay is reasonably varied, reasonably deep ruleset and, most importantly, it's fun. It's the type of game that will help you grow as a player.