Hope it doesn't read like I meant hate to systemd, please let me know where if you feel like I did! I guess some of the cons I listed count as subjective, but I doubt anyone would argue that adjusting a systemd job is easier than cron job :) Also I emphasised that I had non-tecnhical user in mind, who would definitely have hard time understanding what are 'timers', and why their job type has to be 'Simple'.

But I agree that forcing cron into doing what it wasn't meant for isn't probably going to go anywhere. That's why I suggested that using systemd as a backend is probably the most reasonable option after all, if only there was a friendlier tool to make the process as simple as with cron.