1. No, it isn't ridiculous.
2. No, it wouldn't be an easy 'fix'.
3. Rear seat passengers need to be properly briefed - or left on the ground.
4. To fly in the front, occupants would need to complete an extensive simulator and training course.
The Hawk is at is - and has been for not far off 40 years. There is no need to change anything to accommodate 'occasional' passengers - and the RAFAT engineers are given far more comprehensive training than any other Hawk passengers.