In my opinion no HDMI will be a disadvantage, I don't know of any player that allows SD upconversion via anything else. Some claim there isn't much difference if any in PQ between component and HDMI. I personally believe it totally depends on the player and display used. It's been a while since I've looked into this but I also believe I read 1080p will only be done via HDMI.

If standard DVD playback is a concern no current Blu-ray player is worth a crap except the Denon 3800. You need to grab a Samsung BD-P1200 before they all but disappear to rare instances used. The player has it's limits but it's one of the best upconverting standard DVD players made. It has a separate Silicon Optics chip for SD. Current players use a Sigma Design single chip for both HD and SD, and the SD suffers. Reviews show if fails many of the SD video tests and DVD playback is better from cheap DVD players. I just bought a second bd-p1200, refurb.

I'd say your 3910 would be hard to beat and maybe pick up a good BR player and start your transition. Marantz is coming out with a Blu-ray player soon, it's on their website. From the looks of the chip set used it should offer good SD. It should for $2k.