If you feel the needs in efficient proxy workflow, welcome to the club and don't hesitate to submit feature request.
Here is the adjusted to less than 2000 symbols feature request text:
***After Effects style Placeholders and Proxies***
It would be nice if PrPro offered AE style Placeholders and Proxies workflow. There are cases, where they are extremely useful, e.g.:
1. Huge modern formats and resource hungry codecs. Not all machines can easily handle 2k or 4k footages, some can't get real time playback even with AVCHD. Not to mention that CinemaDNG importer was discontinued partly because of inability to get real time playback in PrPro. The issue can be resolved via rendering previews, but that's not always the most efficient workflow.
2. In multicam editing issues mentioned above increase dramatically. Rendering preview for every camera angle is simply impossible. Although PrPro offers offline clips workflow, an editor can't easily see if the clip is currently linked to a source footage or a proxy, and switching between sources and proxies involves several steps every time one needs to switch: selecting assets, making them offline, right-clicking again to link to other media, locating files on a disk; while in After Effects it's just one click once a proxy is set.
3. Adobe Dynamic Link. PrPro communicates with AE projects via single instance of headless AE, which creates a bottleneck and entails the need to render DI for complex comps. Although AE allows to set DIs as proxies and, hence, enjoy the best of both worlds, instantly switching between DI and dynamically linked comp and no needs to replace anything in PrPro timeline, with hundreds of dynamically linked comps PrPro timeline becomes unresponsive and takes forever to render (for my rig test 30 min sequence built out of 935 dynamically linked comps, which are just source footages in their own comps, hence, the equivalent to rendered DIs set to proxies, takes around 27 hours to render, while 30 min sequence built out of the same 935 source footages renders in real time). Meanwhile, PrPro doesn't currently allow to link offline dynamically linked comps to rendered DIs.