The "New" Collector has a lot of issues when compared to "Old":
Classic: Don't have to wait for a GPS connection, don't actually need one. Just tap on the map where you want 50 vertices, and there they are.
New: First vertex has to be GPS only (You don't have a choice), have to zoom and pan for each of 49 additional vertices.
Using the workaround to use sideloaded basemaps (When taking the map offline, select "World" resolution so you can actually use a basemap, then select your offline basemap in the map)....everytime you switch a map, when using multiple maps offline, the basemap always defaults to "Default", which makes sense, it's called "Default", but that doesn't make it any less annoying. In "Classic", whatever basemap you were using in Map 1, is the one you get when going back and forth from Map 1 to Map 2.
I have one map with 4 layers, 2 of which are point. One of the points I turned clustering on, but I'm not getting clustering in New Collector. It defaults to the symbology baked into the service (same on old Collector). Is this something that's being planned (support clustering)? That sure would be handy.
And the problems continue. In "Classic", I could click "On Device", and see only those maps on the device. I could also see the total number of Maps I could bring offline. In the new Collector, "On Device" and available are grouped in the same window, and everytime I restart the app I have to wait for the "available" to load, which is a very long time over crummy Wifi, before I can do anything, and the only counts I get are the number of offline maps in each group, not the total number of available maps. This "New" Collector seems like quite a significant step backward in functionality.