Go through electrics 1st as blocked fuel filters/ pump issues typically will result in misses or stumbling at revs. condenser/capacitors, points gap/age or low coil voltage can all prevent coil charging which shows up at higher revs.
Weber Jets have fine holes and could have a bit of crud, check plugs after a run to see if a plug is different colour to others.
May want to consider long term a push on style EFI filter from a falcon or similar. They are plentiful and offer finer filtering than the OEM style plastic filter when running webers.