I largely agree with your points re infinitive vs. gerund vs. imperative in titles. I haven’t used the full infinitive - “To balance your checkbook” - for years because the “To” is a waste of screen space and adds nothing by way of meaning. I use the gerund, though I can’t give you a reason why other than personal preference. (Your point about the “ing” wasting space on handheld device screens is a good one that may move me away from the gerund over time.) I’ve avoided the imperative form for the same reason you suggest - some readers may take it literally. In a nutshell, I agree with the “keep it simple and consistent” approach.