mephraim
Licensing
I don't think you can license it under MIT if you're using Ghostscript library.
The Ghostscript terms on this are pretty clear, yes: http://www.ghostscript.com/doc/current/Commprod.htm (Ignore the bit about commercial and it is still valid). Since this library hooks into the library API it would not function without GhostScript, so it qualifies as a derivative work. Ergo the entire project needs to be AGPL (or GPL if it's an earlier version of Ghostscript).
GhostScriptSharp is using GPL Ghostscript 9.05 from 2012, which is licensed under the normal GPL, not AGPL as the current releases are.
GhostScriptSharp does not directly link against GPL Ghostscript (it uses PInvoke to execute a DLL that has a similar interface), but the FSF thinks that this still constitutes a derivative work (see also), and to reasonably argue that it isn't you'd probably need to show feasibility that some other non-GPL DLL could be substituted in by the user.
Even if it were acceptable for GhostScriptSharp to consume GPL Ghostscript while being licensed MIT and therefore be incorporated into closed source software, that ignores the obligation to distribute the source code of GPL Ghostscript itself. By including a copy of the GPL Ghostscript 9.05 binaries into GhostScriptSharp and then into any product that uses GhostScriptSharp, people are unknowingly becoming obligated to disclose the inclusion of GPL Ghostscript 9.05 along with its license terms, and make available the source code of GPL Ghostscript 9.05, as described in section 6 of the GPLv3 (Conveying Non-Source Forms).
