Your question made me go to my ARRL Repeater Directory and the suggested spectrum usage for 144-148 Mhz. Of course, these are just recommendations, but I am sure you would want to steer clear from repeater inputs and outputs for CW of digital usage. There is a "Miscellaneous & experimental mode" section set aside for 145.50-145.80, but depending upon your location, simplex could be used most anywhere. I once experimented on simplex with slow scan TV, but only once. And, local APRS is basically a digital mode. 2 meter SSB is popular too. Truthfully, I don't have an answer.
I might add that I know that there is D-Star digital repeater in Dallas, TX. There probably are more.