I've not said a 150/152 can not operate from grass. It is just that even operating from a paved runway you too often have a TOW restriction. I've also done enough time in an asthmatic 152 to know how pathetic their performance is and quite why people describe them as good trainers is beyond me. I've flown PA 18, 28, 32 & 38s, C150/152/172 (various)/206 & 207, Robin DR400 and quite a hours in other more interesting types. The most unpleasant to fly were the C150/152 and PA38. The most useful, from a PPL perspective was the DR400. But it is not a good club aircraft. It needs a hangar and people who will respect it.
Returning to the 172, I've done enough ab-initio instruction in one to know that that they are a good teaching platform. A 172 can lift more from less. Quite how much more it costs to operate than a 150/152 I'm not sure but it has to be worth it. Hatton asked about the best aircraft to start a group with. Any aircraft where you have too many limits is best avoided. One with more performance means more utility which means a better club operation. And as someone said above, it's a shame we have to look at relics for current operations. This is true cost of lawyers and product liability insurance.
PM