I travel a lot for business as well as pleasure (live in SoCal but we have offices in Orlando and Miami) and have TSA PreCheck, as well as Clear. I have both my wife and adult son on my Clear and they both have PreCheck too. As crazy as the MCO security lines are, the PreCheck line always moves very quickly there and honestly half the time I don't even bother using clear at MCO. I'm not sure if it's because so many travelers there are less frequent fliers (tourists) and don't have PreCheck, but even when the regular security lines are huge, PreCheck never seems to be too bad.
I'd get PreCheck first, then decide about Clear. If your CC company offers discounts/statement credits for both, then I'd jump on that. As far as getting set up the first time, it takes about 5 minutes tops to do fingerprint and facial scans, then you're done. Since you'll be getting set up at your departing airport, when you're headed home through MCO, you'll be golden.