Just out of intrest is there a reason your against using LIPOS?
Its a good question.
I am new to the hobby, having raced RC cars in the in the early 00's (NiMH, but just before brushless became mainstream) and for me the fear of LiPo is probably mainly just the unknown nature of them.
Risk of fire is often cited, and is also a consideration, but mainly just not really knowing where to start. As well as having existing chargers for NiMH/NiCad.
I know for cordless power tools they are now mainstream, and also recommended for infrequent use as the self discharge is low.
Looking briefly at what is for sale, it appears that cost wise LiPo appears to be on par with NiMH these days.
At which point while it is a given for power to weight, maybe LiPo is the way to go for most applications now?
LiFe batteries also appear to be making an entrance, and appear they might be a reasonable option for boats?