Doing little surprises for someone, texting them to wish them a good day, etc, is a form of signalling. People like it because they know that you are thinking about them randomly, and that you care how they're doing. If you're simply using an app reminder to do stuff in order to grind relationship points, it has a completely different meaning.
When I’m staring down a long, busy day and she looks run down, I schedule an email a few hours later to say “Hope your day is going well, you’re awesome and I’m grateful to have you.”
When my wife gets the emails, I’m almost certainly not thinking about her. I’m usually at work focused on work.
Am I doing romance wrong?
If it works for you then maybe not.
Personally, I think that if there's time to schedule an email, then might as well just send a quick text message. That's more personal and allows for an instant response. I'd also never send an email for personal communication like that, but maybe that's just me.