Definitely look at what your Staff are interested in and can deliver and go from there.
At my last Sqn we had:
Radios - handhelds (2xRAF Service Instructors on Sqn who made radio lessons really fun, we also used them for events, fieldcraft ex, FA ex etc)
Fieldcraft Kit - webbing, shelter sheets, poles, mess tins
AT Kit - enough to kit out 10 Cadets for full DofE Expeds
Maps & compasses
Flight Sim - next project was to add VR
Sports Kit - rounders kit, footballs, frisbees, hockey kit, bibs
First Aid - stuff for casualty simulation exercises, wounds, blood etc
Outdoor shelters - it was as if I had predicted covid & the need for outdoor classrooms! They were used at events or Sqn BBQs
Air Rifle - we bought the TS25 package from Air Arms and then added on a third lane, an extra air rifle and the magazines to make them multi-shot
I’m sure there is stuff I’ve missed off too. I would have loved to buy mountain bikes but storage of them was the problem.
My current Sqn is no-where near as well equipped, it has a lot of sports kit (including javelins, discus and shot-putts!), a couple of sets of webbing, radios and air rifles. A shopping spree is definitely needed.