There are no plans to drop collada.
In what seems a lifetime ago, I did extensive MH collada export testing when mhx2 went out on its own. We still have some open issues which Joepal has summarized here
http://bugtracker.makehumancommunity.org/issues/1148 but fundamentally it is working fine in the release version of MakeHuman 1.1.1 . Joel had it right when he commented that Collada support is weak everywhere. It's a not so standard standard.
To illustrate. It turns out that when I tried to use a round trip export/import from Blender back into Blender to assure internal consistency (i.e., to have a gold standard) , I discovered that things exported objects did not round trip intact and back into Blender. Blender citizens are working on it. In fact, Avastar's Gaia Clary is spearheading an effort to keep Blender's Collada alive and relevant against SOME voices that seem not to care. Their work can be monitored here:
https://developer.blender.org/project/profile/33/ I have not had time to stay current with their Blender efforts as of late.
For now, our (MakeHuman's) released .dae files import fine into Blender 2.79 and I have typically not had to use any special import options. [I don't use second life, so I can comment directly on that scene.] Again, there is no plan to drop support. But, there is also no plan to redesign anything until other major work on the core application is finished, or unless someone new decided to take on such a project.
All that said, specific bugs on the release code can be posted to the bugtacker, and we'll see what we can do. No promises.