I would like to propose the following improvements to SharpDevelop's search/replace dialog and functionality. AFAIK they are not currently present in SharpDevelop 3
1. allow "search in current document" and "search through entire project/solution" to be differentiated via hotkey vs via mouse actions as it is now. Visual Studio .net provides a good example: you can search document with CTRL-F and entire solution with CTRL-SHIFT-F. I found the need to use mouse to switch between these modes a major hassle when doing search-intensive research work (incidentally, the research was on the SharpDevelop codebase :) ). BTW, I essentially fixed this problem for my own purposes by using AutoHotkey to record a macro that does the switching between modes with the mouse for me, but IMHO this is just lame in the big scheme of things.
2. allow search/replace dialog to be hidden by clicking Escape, including if the cursor is currently in the document, i.e. if the dialog is not selected
3. provide "help" explanations of "wildcard" and regular expression modes of search, ideally accessible directly from the search/replace dialog just like it is in Visual Studio. Incidentally, are those wildcards as powerful as "special characters" used in Microsoft Word and Visual Studio?
4. during long searches through the entire solution (of a big enough codebase) provide a "cancel search" button to abort the ongoing search
5. display number of replaces done (right now it just says "replace all done")
6. support line level search with multiple search keys. In other words, make it possible to find a code line that let's say contains substrings "txtText" and "+=". AFAIK something like that is already done by Google Code but only for keywords as opposed to for generic substrings, plus Google Code is usually not available to people working on their own projects.