So let's say a certain soon-to-release total conversion wanted to use this, have the launcher pre-configured with a set of command-line flags and settings so that it's immediately ready to go, and not mention FS2 at all. Listing TC-specific mods would be a definite bonus.
How much of this is possible right now without changing the source? What would I need to do this?
Removing mention of FS2 will require (some) modification of the source code (change some strings basically).
Having the launcher pre-configured with a set of command-line flags and settings would be doable with some modification to the installer (that is, change some of the profile information that the launcher has by default, though at this time, it would have to be specific to the user that installed it. To allow these defaults to affect all users on a system some modification to the source code would be required (to change the default profile and have the launcher look somewhere else by default for the TC [it currently defaults to nothing]).
I am not really sure what you mean by "Listing TC-specific mods", but I think it does that already without modification.
What are the barriers preventing me from using wxlauncher as part of a TC release?
I would highly suggest looking at a "trunk" build of wxLauncher for a TC release.
The things that are missing for a TC release is the support for the customisation at a TC level (changing the strings).
There is a bug in the handling of profile creation that will blank the Advanced settings tab. jg18 is currently working on a fix for this.
There is no support for the new openal code in FSO. I will be doing the OpenAL stuff in May.
I should be on IRC in about 4 hours, if you want to talk about specifics. Or feel free to PM me with the specifics.