Again, the AGD Audion mono blocks are very light with no heat and class D or not these are the best amps I’ve owned. Just for reference I also own the Coda #16.
Echoing some other views here, it is going to be difficult to replicate the sound of your 30.8 with something light. Any of the amps that I've heard (and I have heard quite a few) which are similar in sonic signature to the Pass are either transistor Class A or A/B designs which are heavily biased into Class A - e.g. the Parasound JC designs. Or they are push pull tube designs. 300B amps like the Arioso don't really sound like a Pass - more spotlight treble, less bass control and extension etc. I appreciate the heat issue in terms of Florida, but I would try to keep the 30.8s if at all possible. As previously suggested, an 25Int might be and acceptable compromise - but even it will be a compromise.