LionChief locomotives run on AC or DC. Anything else is AC ONLY. They send DC packs with the starter sets since it’s easier and cheaper once you outgrow that though you guys need to go AC and get a “real” transformer. CW-80’s are not bad per se but they can have some to be desired. You however should NEVER run a train with the accessory outputs of a CW-80 that output isn’t designed for trains. There’s nothing wrong with using the track output simply raise the handle too full voltage and your off to the races. The MTH Z500 also isn’t “bad” but I think it may only be 50w I’m not sure so don’t quote me. Do keep in mind that Lionel recommends never going above 19V. A MTH brick can output 21V.
If your still wanting to go bigger now will depend what you wish to run. If you still want the capabilities of the having the CW handle but more power try a GW-180. 180W, the other would just be a straight 180w PoweHouse brick witch has arguably the fastest breaker in the hobby. To recommend much more we need more information of your railroad and what you want to do.
CW-80’s and other small transformers make great accessory transformers