Two stupid(?) questions about LAME Options

[BFG]

Hello all. As you can see, I'm new to the boards, but have perused them as a guest for some time.

I'm still trying to learn the ins and outs of audio archiving, and after doing considerable reading I've started archiving my CD collection with LAME, using the -V0 and -q0 (highest quality VBR) settings.


I have two (potentially stupid) questions for those more experienced than I:
(1) Do you see any point in recompressing my CDs using LAME 3.99.5? The vast majority of them are already compressed with 3.98.4. 3.99.5 seems to give a small file increase on the higher quality settings, but I'm really only concerned about the audio quality.


(2) I've noticed that LAME VBR always uses MPEG 1-Layer III bitrates (32, 40, 48 ... 320), presumably because CDs are always at a 44.1kHz sample rate. Would it be possible to combine MPEG 1 and MPEG 2/2.5 (8, 16, 24...144, 160) bitrates in the same file? If so, would those be readable by most players? And what about using freeformat options e.g. 288 or 640 kbps?
I'm thinking that allowing MPEG 1 and MPEG 2/2.5 in the same file, if that's possible, would allow VBR files to be a bit smaller with no quality loss - since silent sections, for example, could be encoded at 8 kbps instead of 32. And it'd be nice to have freeformat options above 320 kbps available since this is for archiving.