> is this worth continuing to invest time into?
well, are you having fun with it and do you see a future or potential with the game? all of your games very much carry an identity of their own and this one does it exceptionally well. if you think you've got something then go for it, but if you see it only as a roadblock for TGO / TSotP, then i think focus on those instead.
if anything, you can always keep it on the side for when you get a workload you don't want to tackle just yet - open this project instead and fiddle around with it or practice art/animations.
huzzah!