Meh. I honestly don't think being able to run while locked on would be such a huge improvement. More like a QOL thing. Sure it would be an improvement but not as massive as you guys are making it out to be. After all, you two are the only people I've ever seen that are bothered by it in any way, pretty much everyone has no problem with it at all and besides, running while in combat looks and feels awkward anyway in these games. Using moves for traversal while fighting is much more stylish, efficient, and faster, I might add.
I made a thread, not too long ago, where I talked about closing the gap with enemies with style, where I went through each DMC4SE character providing examples on how to do it without running, which looks really silly while fighting imo. When every character in these games has a plethora of movement options like Stinger-ish moves, teleports, dashes, double jumps or some way to bring the enemies close to them, the option of running while in combat would really be an incredibly minor thing to add. Doesn't mean I wouldn't want to have it implemented, but at the same time it's not that big of a deal at all imo.