First: what specifically do you want the system to do that it doesn't now, and/or what settings do you need to change in the CA often enough to be frustrated with it's menus?
(which I understand; it's one reason I use the USB cable available from http://www.ebikes.ca/shop/electric-bicycle-parts/ca-accessories/cables/ca-usb.html to hook it to my laptop and use their program https://www.ebikes.ca/product-info/cycle-analyst-3.html#software-setup-utility to make setups to experiment with; it's much faster than the onboard menus).
Regarding swapping one for the ohter, well, they don't do the same things.
The KT LCD only displays the stuff teh controller tells it to, and it cna only adjust settings the controller has built in. It also only works with compatible KT controllers.
If you do have a compatible KT (Kunteng, Kun Teng) controller, then you can look up the thread(s) by Casainho / Stancecoke / etc about the open-source firmware for them, and flash the LCD and controller to that, which will give you a lot more control over the system, if ti's compatible with it. (you'd have to check the thread(s) to find out how that works; I only know it exists).
IF the controller is not a KT, then you'd have to find the LCD that's compatible with that specific brand and model...but even if you do, it will still only let you change the settings your specific controller already has that are changeable, and sometimes that's not much, if anything.
The CA can (may not be setup to on yours) actually control things itself, such as run a Torque sensor or cadence sensor for PAS, limit speed, current, power, etc., with presets and realtime control of one of various parameters, etc. Sometimes this is all very useful, and sometimes it is not; depends on your needs. If you don't need the features it provides, and just need a power meter, then you coudl remove it and replace it with just an LED dot / bar display or voltmeter, like come built into some throttles.
Generally, once a CA is setup to work the way you want it to on a particular bike/trike/etc., you won't need to change settings in it's menus. If you need to change certain things regularly, you may be able to setup presets for them so they automatically all change; the presets can be selected via a switch or buttons on the handlebars, or the CA front buttons. If there's one setting you regularly change, you may be able to assign it to a knob on your handlebars.
If you need help setting up the CA the way you want, you can either post what you want, and what you already have, here in this thread or in the CA 3 beta thread, and someone may be able to help you work out exactly what you need to change to do it. Or talk to http://ebikes.ca that make the CA, and see if they can help you directly.
This https://endless-sphere.com/forums/viewtopic.php?p=571345#p571345 thread with the UUG by Teklektik is a pretty good help in getting it all setup...but it takes thorough reading and step by step implementation to make sure you don't miss something, if you h
