Free to Fly
If you wish to gain your Instructor Rating based on your PPL and therefore Instruct for free, then do so. It matters not what the FEW self interested think.
The industry desperately needs people who want to be part of a club for the fun of it and teach fellow club members FOR FREE! Thats how it use to be until the wannabees took control but sadly aided by ill judged support from the Belgrano. They too, the Belgrano, seemed to think that the flying instructor role was only a path to the airline job.
Many flying clubs are on their knees and surviving by the skin of their teeth and many are closing down. The only way flying will be revived in this country is if we can get back to the 'club' where members share flying as recreation and a common genuine interest.
You sound like the perfect fella to be an Instructor - do it!