New IQ panel - what else to replace?

Hi fellow Alarmers – our IQ Panel 2’s battery just expanded and split open the panel. I figure that the panel has been damaged and trying to replace only the battery would be a waste of $.

But if I buy an IQ Panel 5, what sensors will I likely need to replace (due to incompatible Z-Wave versions or whatever else)? I have what I assume are legacy door sensors, motion sensor, and fire alarm (which just listens for the sound of a standard alarm). We bought all of those in 2020 I believe.

We also have a Schlage Connect Z-Wave lock which has worked well with our setup so far. It’s from 2019 – could it also be a legacy version of Z-Wave that might not be compatible? It’s a main driver of staying in the Alarm.com ecosystem, since if we went wifi we’d have to replace it along with everything else (or buy a bridge).

Our Alarm.com thermostat also died a while back. Can I buy any Z-wave thermostat or do I need to go with the Alarm.com one? I hear good things about the Honeywell TH6 (we have a heat pump and a natural gas furnace).

Thanks!