Conclusion from slack thread:
https://ibm-cloudplatform.slack.com/archives/C0M053VPT/p1559587807036800
Investigate/look-into:
Related to buttons:
Adding some screen shots from the discussions related to some of the above (mostly progress modal);


It's worth mentioning, that with the progress modal variant, form elements are often par for the course, So longer modals are typical (sometimes wider)
Added detail request for Single acknowledgement modal: https://github.com/carbon-design-system/carbon/issues/2924

Video of use case where we would benefit from a single button "Continue" at the end of progress modal.
Progress.mov.zip
Here's WH's requirements around modal behaviors: requirements.txt
Additional investigate smaller modal max-width, for "dialogs" or "message boxes"
https://ibm-cloudplatform.slack.com/archives/C0M053VPT/p1562701030157400
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keepalive-bot

Is there any discussion of providing a more traditional modal footer where buttons do not take the whole width of the dialog? It is quite different than the Carbon 9 modal or any other modals that i've seen from several applications / websites, wondering if there has been any user testing or reasoning behind going this way rather than the common approach.
We've marked this issue as stale because there hasn't been any activity for a couple of weeks. If there's no further activity on this issue in the next three days then we'll close it. You can keep the conversation going with just a short comment. Thanks for your contributions.
keepAlive[bot]
this one has garnered a lot of debate. potentially a good candidate to prioritize?
Its top of our component enhancement list, the team just hasn't prioritized that project. Hopefully we get to it soon. Design's trying to get enhancements prioritized.
also see #3509
Related: Nag Modal
https://github.com/carbon-design-system/carbon/issues/1478
We've marked this issue as stale because there hasn't been any activity for a couple of weeks. If there's no further activity on this issue in the next three days then we'll close it. You can keep the conversation going with just a short comment. Thanks for your contributions.
keepAlive[bot]
Closing as modal have been updated in v10.8 and resolves many of this topic. Any items not covered my the modal updates can be opened as individual issues.
Most helpful comment
Its top of our component enhancement list, the team just hasn't prioritized that project. Hopefully we get to it soon. Design's trying to get enhancements prioritized.