I think probably the best method of controlling animals would be to make it as close as possible to vehicular movement, perhaps with some niggles to, for example, account for animal stamina and, well, intelligence. The interface could be whatever, solong as the actual controls for movement where sorta close. Work on semi-intelligent self-control for horses and whatnot might even lead to, for example, NPC control of vehicles, which would be rather awesome.
However, speaking of animals(and to a lesser extent, NPCs), has any effort been put into animal-powered vehicles and/or the ability to choose professions or scenarios that start you out with vehicles and/or animals? Also, is animal handling intended to be a new skill or tied into existing ones, or even not tied into any skill at all?
The system would mean that vehicles ( carts ) could be attached to an animal and dragged, yes, that is one aspect that is definitely wanted.
That was much easier under my "horse-as-vehicle" implementation, but still do-able otherwise.
Starting with an animal with a scenario has been looked into , but is not currently being worked on by anyone as far as I know.
There are plans to make animal handling and taming more involved. a multi-stage process of taming ( think Rimworld perhaps ) where their utility is enhanced with each step - and that would tie into horse-riding. I will probably look at that myself, after this.
The benefit of not making the horse a type of vehicle is that then the movement could be a hybrid of the horses decisions and the human guidance, which is more realistic, the horse could auto-path around obstacles, and possibly, if not well-tamed or obedient, could throw the rider or be difficult to control.
Animal handling dosnt fit into any existing skill, although I suspect Survival skill will be a placeholder for the time being.
There is early nebulous talk of a "proficiency" system, separate from skills. That you either start off knowing or you don't, think lockpicking, surgery, other complex niche knowledge, this could also potentially encompass animal handling in the future - this would then be tied to starting profession ( a farmer would know animal handling, a burglar might know lockpicking etc ) - but it's just talk at the moment.