You’ve received some good advice so far and I’m sure others will be weighing in.
And remember, there is no right or wrong answer. You have to decide what’s best for you.
Read through your initial post a few times and here’s what I would do if I was you. You obviously have a good roster of conventional runners. I’d look through what Lionel offers in the Lion Chief Plus line (plenty of steam and diesel choices) and pick up one of those. You can run these conventionally or with the supplied remote and you are not committing yourself to a higher-end command system. LC+ gives you a smaller taste for now while you ponder your future options. The nice thing is you can probably pick up some of the previously released LC+ locos at attractive prices.
Good luck.
