I have an advantage that most of you don't. Besides having my own hives, I have worked for a commercial operation for a while also. Therefore, my views on certain things can give perspective from both sides of the coin, both commercial and hobbiest.
Please don't take this personal Robo, as it is not my intention to single you out, but I have have a different view on some of the suggestions you offered.
The amount of comb you would "save" scratching vs. cutting is not worth the additional effort.
Having done both in a commercial operation, scratching is much faster.Capping Scratcher
If your not careful with the scratcher, you can easily damage the comb walls.
I haven't seen this to be any disadvantage, even when the cell walls split, the bees are quite adequate at patching if needed.
Would you rather leave a trail behind the hot knife, of burned honey, and mix that in with your good honey? I personally sell raw honey, not raw honey with a burned flavor.
Using a knife also allows you to "true" up your comb.
This can also be done by scraping with the capping scratcher.
Even if you cut with a knife, there is still enough comb left to raise brood.
Are we talking about honey supers, or brood comb?
Put them in a sieve and let them drain. you can put them in cheese cloth and add some weight too if you desire.
Cheese cloth leaves behind microscopic fibers of cotton, upon which your honey will start to crystallize, let alone taint your honey.
Heat and honey don't mix, so just melting them down and then reclaiming the honey is not the best, unless you plan on feeding it back to the bees.
Never feed heated or old honey to the bees...Heated honey and bees
If you say now that heat and honey don't mix, did you not mean a hot knife in your previous suggestions? If you meant a cold knife, then again I would still have to argue that a cold knife would do more damage to the cell walls trying to uncap the frames.
I use both the electric uncapper and the scratcher.
In a commercial operation, I have found that way too time consuming to use the electric uncapper(hot knife) for the high spots, set it down, pick up the capping scratcher to finish the low spots, and switch again to start the next frame? Maybe if I only had a few hives and hated to see my hot knife getting lonesome, otherwise why not have just one tool in your hand, and use a capping scratcher exclusively, for the advantages mentioned above.