I used to play my favorite route first, as long as it wasn't locked. But later, because I couldn't get the endings I wanted, I started using guides. After using guides, I couldn't help but follow the recommended order, and that's how I became a completionist.
If there are no route locks, I prioritize playing the characters I'm most interested in. If there are locks, I follow an order that lets me unlock and get to my preferred character as quickly as possible. That said, the character I'm initially interested in doesn't always end up being my favorite; since I usually complete every single character's route, sometimes other routes end up being a pleasant surprise.
I choose Li that catch my eyes first. With interesting personality and how complicated his mind is. But if there's no have character like that, i just pick based on what design type i like
I'm usually a "save the best for last" person, but sometimes it gets tricky when my favorite is the exact opposite of recommended route order. (I'm keen to follow writer's intended progression!)
The character who looks like the obvious first route turns out to be last or last before locked, while the one that seems super story-heavy is recommended first. These happen way more often than I'd think. ₍ -ࡇ- ₎