24kbps? DOn’t you mean MBPS?
That’s not a big compression ratio in MBPS.
In KBPS… …HOLY CRAP! That’s a lot of compression for a 720 video!
What are you using the Video for? This will determine a lot about your export.
EG
Blu-ray max MBPS is 40 for standard Blu-ray, and 50 for AVCHD (which is almost no compression for 720 and a huge file).
DVD is Mpeg2 and 15 max. FOr Bluray5\9 the h.264 is 15 max, but you should set no more than 12.
Youtube…
This one varies. How much quality do you want? How much do you really need? At 720, a 7mbps is great, and loads quickly. Think about it… Net speeds are 10-20mbps for a broadband connection on a budget. IF your video takes that, there’s no room for other website data or throughput, so it will buffer… …and buffer… Set your video below that threshold by a good amount. Especially since budget internet is in FAMILY (split up connections on a router) homes (Ie shared bandwidth).
For 1080 7-15 is the max I would go.