If you have a v1 keypad then ST won’t be able to help there but with the v2 and v3 keypads it shouldn’t be an issue. If you have access to RBoy Apps, you may also want to check out some of these apps which can take advantage of your v2/v3 keypads features:
Device handler to use your keypad: [RELEASE] Enhanced ZigBee Keypad Device Handler - Centralite, UEI, IRIS, Xfinity, Scout
A security app to replace SHM security module or use in conjunction with SHM along with a keypad: [RELEASE] Security System: Intruder Alert with Actions
A lock manager which can be used with keypads and other apps: [OBSOLETE] Lock User Management (LUM)
An app to leverage your Alexa setup to create custom notifications and also use your keypad as a chime: [RELEASE] Door Chimes and Notifications for Doorbells and Sensors
If you have a v1 motion sensor I don’t believe it’ll work with ST (Hubitat has support for that). However the rest of your devices should work just fine. Most should work without any custom device handlers but some may need one to get the full functionality from them. Which devices are you having an issue with?