GtE I find it very sad and somewhat disingenuous of you as a flying instructor to post on an open forum that you find both the C42 and the C152 boring.
There are 173 C42 and 251 C152s on the UK register and I don't think that any of their owners or others who do enjoy flying them gives a to$$ about your finding them boring.
People who are thinking of learning to fly really want their instructors to show a level of maturity and encouragement and have some passion about aviation.
These days it is hard enough to get new students in through the front door but if they are confronted by self opinionated part time instructors then they might well walk out again.
You do yourself no good making just comments.