And/or increase the range, but require that you keep charging until you run into blocking terrain or another character.
I'd say that could be a new card say Wild Charge. Unlimited distance but as you say much finish on blocking terrain or another character.
I would not normally reply to my own post but I think it may get looked at more this way. If there was to be a new Wild/Reckless Charge card then the charging character would also take some damage to compensate for the Unlimited distance.
Maybe if you added Halt at the end of the run, but I think it would be too powerful otherwise, even with taking a bit of damage.
"Too powerful" can be compensated by card suites, unless you're talking about some truly game-breaking stuff. On the present maps, Sprint is very nearly an "unlimited Move card." I don't think that this strictly-limited card (it has end-of-move conditions just like Cautious Sneak) is game-breaking. But then, I'd still suggest limits to "unlimited" cards because it's always weird to balance a qualitative thing like limited/unlimited. Move 8, like Sprint, could be enough.