I think your effort would be better put towards an enclosure for the whole printer if you don’t already have one.The radiant heat loss of the bed will become a good thing. Lots of people add additional heat time to give the stagnant air time to heat up the enclosure. As others have said though it sorta depends on what you’re printing mostly if it matters at all. PLA is such low temp it’s not difficult for the machine to maintain at all. If you’re doing PC or nylon you may need every advantage you can get.

For the adhesives conversation, there are quite a few that can cope with high temp. Silicone is probably the best in case you regret it. Other glue could take a coating of your plate off.