The core of the VGS output is the GS. GICs are essentially AEF dressed up as training and since the VGSs are staffed by volunteers with instructor training in-house, it gives those junior staff a chance to practise and hone their instructional skills, and all adds to the stats. However, the trend is towards a more "professional" organisation with increased administration and over-sight. It would therefore seem appropriate to change to a full time VGS organisation - employing paid staff to delivering GS training on the weekend during school term times and throughout school holidays. To match current output, the organisation would need to deliver approx. 2,500 scholarships per year, or 50 per week. You then build your organisation around that requirement. AEF flying would be better handled by AEFs. A "professional" organisation also reduces the in-house training burden, allowing effort to concentrate on the key deliverables.
Additionally, the proposed re-introduction of the IGT would not be a sensible move. When the IGT was first introduced, students were too young and the IGT training still had to be repeated when they returned for GS. Far better to just stick to the GS.