Hi Ford
I don't think you'll get much joy with upgrades at this scale - there just isn't a hobby following that I can find (they're more of a toy).
There does seem to be a gap between the very popular 1/35th military modelling - with 1/24th R/C being a hobbyist black hole - and the 'standard' 1/16th R/C offerings that 98% of the users on this forum and around the globe adhere too.
There may be a way to make the turrets 360 see:
viewtopic.php?f=195&t=12215 if it's a similar setup?
There are some electronic offerings from
http://35rctank.com/index.html that may be adapted for the VSTanks (you'd have to use a different Tx/Rx), and for waterproofing I'd use Conformal coating on the electrics - but again, you're going to send a lot of effort on something that will at the end of the day still be toy grade rather than a scale model!
(Yes, I do realise that 1/16th is still a 'toy'...)
