- I know there's a lot of interest for KVNY. One option is VNY towers, ground and clearance deliver
- I have also been testing the SoCal Tracon frequencies in the area (135.05, 124.60, 125.50, 134.20) and Los Angeles Center (125.80) and these come in pretty good. This would probably be more useful to my private and instrument students
- I could do some combination. Have KVNY + a SoCal freq and KBUR + a different SoCal but when it's busy it might be way too much congestion
In my opinion I prefer never to combine a clearance delivery with tower and ground, since CD will dominate the feed and prevent much of the activity of the other frequencies from reaching the LiveATC outbound feed. Additionally, after a period of time in listening to it CD activity becomes somewhat monotonous.
For instrument CD training, someone else here suggested a month or two ago to switch the feed to a CD-only freq for three hours or so, and then edit the archive (of silent spots) and post it to the audio forum here. This clip can then be downloaded by instrument students looking for CD copying training.
My second opinion is to not load up a feed with too many frequencies (as pointed out in your third bullet) since that will make it all but impossible to follow any of the activity past one ATC/pilot exchange.
So, this leaves a tower/ground/(maybe approach) feed or a SoCal feed. Personally I lean more to the approach/tower combined feeds because of the varied scenarios. FWIW...