Ron, these are all great ideas, most very useful. In the pop-up box, frequency-of-service indications by carrier would avoid an immediate need for flight numbers, times, and aircraft type. List # of trips per day or week, and seasonal date ranges if appropriate. Also, I wouldn't list codeshares in the first tier, just airlines that operate the equipment.

If feasible, it might be fun to indicate frequency of service by all selected carriers between selected city pairs by width of line, or color code.

I look forward to your product. Can't offer much technical assistance, but if I can put in a good word here or there, let me know.