This is closer to my area of expertise:
And these are all the kind of mistakes we all made when we started shooting people w flash.
You’ve put loads of effort into location and styling, but no thought into the lighting - using simply the exposure answer of ‘enough light’ rather than ‘complimentary light’. The subject is fighting the surroundings for attention because she’s all muted colours and you’ve blasted some vibrant green with flash.
Your model would benefit from being short lit, and could have done with some makeup (I appreciate there’s a load of idiots online who reckon that lighting and makeup can be added in post, but realistically it’s quicker and easier to do it prior to the shoot. )
TBF this might entail some investment in lighting rather than camera gear, a couple of Godox AD200’s, an xpro transmitter, a softbox, brolly and a couple of stands would be a great use of most of your budget.
Selling all your gear and investing in the latest camera and a fantastic lens would not change that shot one iota.