After having worked on a film project or two, I've come to the realization that Mixcraft needs a kick in the pants when it comes to the marker system. The biggest issue I've noticed is that I cannot reliably use Mixcraft's markers to make cues for syncing tempos to a video clip if the perceived tempo of the video changes at all.
Essentially, my #1 is this: Allow Mixcraft markers to either lock to the bar:beat:ticks position (lock to measures) or to lock to the timestamp. If markers could lock to the timestamp instead of tempo, then there wouldn't be any painstaking marker wrangling markers back into sync with the video if the tempo gets changed on one of them (the current system only syncs to bar|beat position, so if I were to place a marker at a spot three minutes and five seconds into a video clip and then change a tempo on a preceding marker, then the most recent marker will no longer be at 3:05.00, but somewhere else entirely).
Secondly, I'd like to see Mixcraft handle plugins a little bit better. While the current plugin management system is a wonderfully huge improvement over no system at all, it would be really helpful to have additional control over the plugin collections, notably sub-categories/sub-collections. It would be fantastic if Mixcraft allowed you to have a custom collection of, say, reverb-only plugins, and then have that custom collection sorted by manufacturer or whatever sub-collection organization system you'd like (e.g. you have a lot of Waves plugins, so you designate those to a collection called Waves Plugins, but then you want to organize that collection into effect types like compressors, reverbs, channel strips, EQs, etc. Or maybe you want to sort your Waves plugins by whether or not the plugin is a mono or stereo plugin, so your Waves collection would be sorted into those two categories).
Finally: multichannel output support. Even if it were something rudimentary, having support for output types other than mono or stereo (LR) would be great: LCR, 4.0, 5.1 Surround, etc. As even many desktop computers ship with OEM motherboards that have surround sound-capable audio controllers (with the necessary 5.1 pin-out, usually L+R/Center+Sub/Ls+Rs on three headphone jack outs), allowing Mixcraft users to work with beyond-stereo output configurations would be an excellent touch.