I wouldn't be as prescriptive around %'s of FTP, and I would certainly not recommend just going straight into "lots of sweetspot". 45 minutes sweetspot building to 2.5 hours of sweetspot three times a week? You will burn out by Christmas if your zones are correct.
If you've just got a power meter then that's going to be really handy for pacing once you've got used to using it, and eventually you might want to do some testing to get your zones.
For now I'd probably continue to ride consistently, with a calibrated power meter, and use RPE for a few months. By all means do some Z3 and if you want then put some long blocks in.
I wouldn't be as prescriptive around %'s of FTP, and I would certainly not recommend just going straight into "lots of sweetspot". 45 minutes sweetspot building to 2.5 hours of sweetspot three times a week? You will burn out by Christmas if your zones are correct.
If you've just got a power meter then that's going to be really handy for pacing once you've got used to using it, and eventually you might want to do some testing to get your zones.
For now I'd probably continue to ride consistently, with a calibrated power meter, and use RPE for a few months. By all means do some Z3 and if you want then put some long blocks in.