Well I have 4 arrow keys, amongst over 100 assignable others, that aren't adopted as they are the foundation. I just think it's an oversight in a constantly changing application that just my opinion, is going to have a similar effect to the CAD industry that Android has had to personal computing...if I could get Ubuntu on my beastly Droid TV Box I'd probably be typing this message on it right now 
I still feel like I'm supposed to be wearing V.R. gloves and goggles when I log into Fusion. When I went into the pros/cons and F360 vs *insert industry standard app here* on numerous forums or other forms of industry published opinions, some if not many people ultimately berated it as an amateur to small commercial enterprise oriented application that for a true professional, should be avoided. Well sorry but I know quality and cutting edge when I see it vs yesterday's big boy. I would be dumbfounded if in 3-5 years F360, or at least an Autodesk application, isn't dominating the others.
I think updating for the arrow keys and adding an assignable hot keys feature to the preferences menu would be a good supplement. The fancy, nimble gadget is something I'll invest in when I'm not weighing financial options of what is the appropriate investment for me in my current goals and living situation. I often find myself looking for hardware options to mousing and keyboarding things for various applications such as DAW and VSTs. In that I own a lot of useful gadgets as well as crap that sits on a shelf or in the basement.
As far as the cost well a product is worth whatever the manufacturer decides, and I won't get into a designer's/inventor's lack of power over intellectual properties smh, so it's whatever people are willing to pay. The brains behind it and fringe customer base are also an obvious factor as well.
All that said I've had some video and audio editing interfaces over the years with similar mechanics and features that were $50 and under. If I were competent in java I'd buy a used USB midi controller for 20 bucks and write a custom driver for it until I'm willing to drop some $ on a connexion.