-As round-ish (wide and short) as possible for an oval (so that people can see each other without turning their heads, and self-dealing could still be possible for a short table for 8).
-Very slightly raised (if at all) rail. My assumption is that the rail should sit at 10-chip stack height at least (or whisky glass height coming out of a playing-surface-based cupholder- see below).
-No wooden racetrack, unless it's covered by something softer and quieter, like leather(ette).
-Yes to cupholders IMHO, either on the rail or on the playing surface (old fashioned short whisky glasses would stand up to just the rail's height). The latter case requires a really wide table (48in width for an oval, or 55in for a round one). At any rate, no tall glasses should be allowed on the table. Cans are safer but should be banned for aesthetic reasons.
-Betting line is of great importance IMHO, for game education, discipline and order, and that's the only reason to not go with Suited Speed Cloth (you can only paint a betting line on the latter, with a good paint marker and lots of craftsmanship).
-LED Lighting: I don't know; I 've never played on a side-lit table. Could be useful if the lights faced low and did not glare, just to help with additional lighting for peeping cards. Aesthetically, not my cup of tea, but I could be converted.
-Felt color: On the darker side, to provide some contrast with the cards, and reflect less of the (required and supposed) very strong lighting provided from above.
Careful when designing felts in relation to chips and vice-versa; it would be stupid to have $25 chips and felt in the very same shade of green.
And, no busy themes please.
Finally, here's a table I adore. Image can't be copied, so it's table #64 , column A, row 22 (it would have been better with a slightly raised rail)
http://www.tables-de-poker.fr/index.php?option=com_content&view=article&id=130&Itemid=283&lang=fr
It has been the inspiration for my much smaller (50.5in) round table