If you're used to a certain way of playing, play it that way. I know a lot of people say you absolutely need to have macros and customized things, but I've rarely used any except for custom emotes.

I also play keyboard only. No mouse for me, unless I need to tell my fairy to go somewhere or I need to click on that one superbomb in Titan Ex without having to tab through a million targets.

The default keybinds make a lot of sense. This game is really easy to control, so I wouldn't worry too much about it.