If you want to keep with the BIAB, i'd suggest spending it on equipment that will increase your consistency.
Pot insulation
Temperature probe/s
Digital pH meter
Water filtration/treatment
Definitely a wort chiller
A vacuum sealer, so you can buy bulk hops and not have to worry about them oxidising
I think its probably been said a few times, but seriously, a keg set up is literally the best thing you can do for the longevity of your hobby. So many people give it up because of how tedious washing and cleaning 60x bottles for every brew becomes. Especially when not every brew turns out to be the best thing since sliced bread. I presume you use the STC fridge for fermentation? - why not use it to hold a keg when not being used for fermentation? You can always store the keg/s at room temp while the fridge is being used for fermentation
J