Intervals.icu

Pros

• Intervals.icu for CTL/ATL, TL, training stress, form, load, and performance modeling ... Intervals.icu is used by thousands of competitive athletes every single day. This is not fringe software.
• for the training plan. https://intervals.icu or strava for the logbook.
• Use intervals.icu or runalyze if you're a data freak both these let you really look under the bonnet.
• Parent context: Does intervals have ‘best efforts’ or similar? I do like that on Strava. Reply: Roughly 10x better than strava in that area.
• It has all the bells and whistles, extremely customizable, syncs with an ungodly amount of devices, apps, is constantly adding support for new features, devices etc.

Cons

• for me personally it’s oddly verbose and I struggled to even find the builder on their website.
• Have you looked at intervals.icu? I've only used it with Garmin, but I think it can sync Suunto and Wahoo.
• Intervals.icu defaults to 147 as the top end of my Z2, as defined by Andy Coggans method, but if I switch to Joe Friel's method, Z2 only starts at 144 and ends all the way up to 159...
• after several other apps (apple_health, intervals_icu) i started using obseed_me a while ago and get a lot of value from it. i can really dig deep through my data there where the other stayed pretty shallow