Okay, I know the correct term is Charge, but I misremembered it once as Ward (like Robin (all however many of them there are at this point, and the other sidekicks for that matter) is Batman's Ward) and now that's just stuck in my head.
So, to sum things up really quickly: Bodyguard is cool. Mobile Protection is even cooler (and a nice answer to the 15-foot radius of Champion's Reactions). Only ever being able to have 1 ally you can actually move to cover, with a 10-minute time to change which ally that is is less cool. It basically means the entire party has to be bunched up on you except that one special someone, or you just can't use your main feature.
So the easiest way around this would be to just separate Mobile Protection from Bodyguard, and just make it a thing you can do any time you Intercept Strike (kinda like Get Behind Me! has). But that's also kind of the too-easy answer, and still leaves Bodyguard itself super limited in usability. So I figure my alternative would be to just upgrade Bodyguard (either as part of the feat itself, or a later follow-up) so that you can just designate more than one Ward at a time. When? Well personally I'd probably go for level 8 (same time as when Group Taunt comes online, so you can favor either drawing more ire or guarding more allies. Kinda fits with the whole "Offensive vs Defensive" lean of the Threat Techniques even.)