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Wow I just found I got negative votes for this idea! I believe, actually this problem is only experienced when you have ~3000 notes like I have...

Imagine there is a printed book of notes, one note per page, and when you are
referring to and reading one note in a particular page (say page 65) then you are forced to put back the book (due to external interruption) but when you come back, how do you resume reading the same note? If you remember page 65 was the page where you left off reading, you can quickly return to it...
Here's another use case:
If there are notes titled:

"Getting PR for your startup"
"Getting publicity for your startup"
"Getting press for your new business"
"How to get PR coverage for your startup"
"Generating buzz about your business"
are the same thing.
These notes could be tagged with the same tag, to 'group' them
but it would create an extra tag visible in the "tags" sidebar.
To avoid this we can either link them together (In-Links) in the body text of the note, or we can define semantic 'sameness' in config file as above.

Readers please also refer, my other post
about "Linking between notes" (In-links)
http://roadmap.cintanotes.com/topic/103847-linking-between-notes-from-inside-note-text/
which is another way of addressing the problem (absence of semantic FTS3 search in sqliate)
Good idea, You can see this type of 'edit settings in the application itself' in action in Firefox - if you enter about:config in the url bar, in Firefox, you get a list of settings to meddle with. Settings can be grouped using firefox settings -like hierarchy using 'dots'-
example
editor.singleLine.pasteNewLines
Firefox also brings the settings listings search results from all the settings 'as you type'
I dont think 'replace' is as necessary as 'find' is when it comes to note-taking. This isnt intended to be a word processor. But I really need (and I believe everyone who takes a decent amount of notes would also need) the Ctrl-F functionality in notes so I can quickly go to a specific place in the note. I believe you can give a higher priority into making Ctrl-F work inside notes, atleast in the next version?
Complicates things -creates too much to worry about:

-how to 'export' notes that contain attached files? As one big binary blob (.dat or .db)? The current single txt-based export file is readable with any text editor. The binary blob will be unreadable outside of CN. What if my system crashes, all my important notes are in .db format that only CN can read (proprietary format) and CN website is down so I cant download CN? Any departure from the current text-based export format (txt/xml) makes me uncomfy.

-what happens if user imports some notes and some of the 'attached' files from the notes being imported have same names as those currently in the 'special folder' and have an earlier modification date. Will CN overwrite the files in the special folder.

-should CN make a copy of attached files to store in its 'special folder'. What if I edit an attached word document from the filesystem, not through CN? How will CN know to 'sync' the changes so the newest version is always maintained in the notes attachments?

All these issues can be solved, code can be written to handle these conditions, but it is going to increase the size of the executable - it will no longer be as lean and fast because it has to handle all these conditions - code bloat due to scope creep.

If people really want file and image as notes attachments they can simply reference the file name/location as part of the note.
It is complication of UI. For achieving the same effect of pinned notes, simply tag the appropriate 'frequently accessed' notes with '#PINNED'. Then #PINNED will appear at the top in the tag sidebar and when clicked it will display list of all pinned notes.