More forgiving on nosewheel landings? Well, that about says it all, doesn't it? Why not make it more forgiving when running into brick walls or trees? That's somewhat like saying an car with airbags is more forgiving when running into the back of a bus.
Don't make nosewheel landings. Don't allow students to do it either. A student properly taught won't do it. The problem comes of failure to properly teach. THe firewall will bend just as eaily on a 152 as on a 172 on a hard nosewheel landing, and it will do similiar damage to the engine mount. It will also damage the strut, and wreak havoc with the Lord shimmy dampner.
Do you honestly believe that Cessna stopped production on the 152, or didn't resume it, because of safety issues? You're far too new to aviation to make such ridiculous insinuations if you really don't know. It's a matter of economics. Strictly economics. The 152 has never been considered a safety risk, and never will be, except by those who lack the basic skills to operate it safely.
Do you really believe that if the engine has "one little burble" on takeoff that "that's it?" Come on! You probably don't require students to land without power, or pull engines away from the airport, either. I'm reminded of instructors I've seen who ended up in a spin with their students, and came back to the office white as a ghost and shaking. Such folks have no business being in the air with a student. An instructor who is afraid of the airplane shouldn't be in it.
The 152 has a fine climb rate for a trainer. You're perhaps thinking of a 150 at higher density altitudes. In any event, 200-300 fpm isn't a bad thing, especially in a trainer. Frankly, I operated a large four engine airplane professionally that could only do 100 fpm when loaded, and did it quite safely. If I had only experience in aircraft with ample performance, then I'd have been in a world of hurt. However, I came from a background where my training used airplanes that required a mile or so after the runway just to get up enough to retract the flaps and climb over the powerlines and be on my way. That's where training begins...when the student doesn't have everything done for him or her.
There's nothing wrong with a 172. There's nothing wrong with a 152. To make the suggestion that the 152 is remotely dangerous shows a great ignorance, and suggests a deeper problem than simple distrust of the machine. Thousands upon thousands of instructors, and hundreds of thousands of students, have flown in that airplane for hundreds of thousands of hours...with little or no complaint.
A poor carpenter blames his tools. It's not the tool.