Based on your trains listed just get a ZW. See how you like the reliability and simplicity of your current trains and the ZW transformer. It has four variable controls and enough power to launch your trains into the neighbors house.
You have a lot of research to do before going into the PS-3, PS-2, PS-1, DCS. Legacy, TMCC, Odessey, sine wave or clipped, cab control 1 versus 2, and DDC, worlds of fancy electronics and fancy high priced trains. People have written books on how to operate the fancy stuff. It's very expensive and prone to failures. Just poke around this forum or google to get a taste of what you would be in for.
If you later decide to leap into the fancy trains and electronics, then the ZW can always be used to operate your lights, accessories, bldgs, etc. You will not have wasted any of your money.
Put an ad in the wanted to buy section of this forum if you want a ZW. You should get a ton of responses.
