Hi Keith, as other posters have already mentioned, the age of the A/C system is what it is and likely was disclosed to you in the Seller's Disclosure - if it is working, budget for the possibility of replacing it in the next 5 years. If it isn't working then request that it be repaired - systems should be in working order, and so this would certainly be a reasonable request.
Everything you mention is correctable by the seller or by you - so nothing strikes me as a huge problem. The radon is considered an environmental risk and if over the acceptable level of 4.2, I would expect to see you request remediation at the seller's expense, with retesting also at the seller's expense and generally done as a part of the remediation to be sure the cure brought it into an acceptable range. And incidentally, once done, you can rest easy, system in place, radon issue addressed, you need not worry. Remembering that radon is a fact of life in NJ (at least in this part of the state) and a gas that can change and a gas that you cannot see or smell, I'd encourage you to see the upside of the downside of an elevated reading.
The grading - you can take care of this and being sure the grading is correct around the house is smart maintenance. Can you ask the seller, sure, although it may not pass the structural, safety, environmental hurtle....but when it comes to the inspection contingency, "the buyer has the right to ask, and the seller has the right to respond". I do believe that a handful of meaningful requests will be far more likely to be addressed than a laundry list of every notation on the report. The inspection is mean to catch the big stuff and provide a terrific and indepth education on the home you are buying.
Another idea to discuss with your agent is the possibility of a home warranty to address your concern about the age of the mechanicals/appliances - if you successfully negotiate its inclusion, the idea is that it would be paid for by the seller and transfer to your name at closing and be effective for one year from close.
Good luck to you!
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