20 year Prelude? Wow, one of the best of that day - always wish I had gotten one of those! Instead I stuck with the less expensive Civic and Del Sol Si models.
I'm with you in the Medicare crowd & wanting all the senior nannies I can get!
With a budget of $40K, willingness to buy used, and no MPG concerns there are quite a few under 7 second cars available. Given that you are not high mileage driver reliablity is less of a concern. Adding the smart safety features does winnow out a few. I'm more of a small car guy so I stick with what I know the best and let some of the others tell you about the bigger rigs
Assuming your 65+ years don't deter you from a low slung car & since you 2 seats are enought I'd consider the Subaru BRZ, Subaru WRX, or Toyota 86 as fun corner carvers to replace your Prelude. These also come standard with a pretty complete set of automatic safety features. VW GTI & Audi A-4 also come to mind with the primary drawback that you have pay extra for some of the safety features such as adaptive cruise control. Last but not lease, especially for a former Honda owner, the Civic is gettng great reveiws & the new Turbo is fast -- as long as the some of the ricer dodads they have regretably attached don't turn you off.
If you really want to go all out performance in senior years and don't mind modern Detroit Iron i'd suggest the current crop of V8 powered pony cars. Their primary shortcoming is that they fall short of the Japanese & Korean models when it comes to driver nannies. The Dodge Challenger hits the target best in stance and style, plus is reportedly the most comfortable. The Mustang would be next on my list. Camero has the speed and handling nailed, but the gunship style tiny windows would kill it for this safety conscious senior.
So that is my starter list for you. Sounds to me like you're potentially in for a fun time of driving some quick cars. Would love to hear what you settle on and why.