Combining CharacterViewer with FontBook in Yosemite I used a OS X 10.5.8 system for several years and now I am using a new laptop with
the latest Yosemite.
 I find some features of the older system are much more powerful than the newest one.
 For example, the Character Palette of my old computer is like a combination of 
strengthened versions of today's CharacterViewer and FontBook.

The CharacterPalette of old could display all the characters (with their Unicode
info) of a given font in a FontBook manner and still fully interact with any text editor.

Today’s CharacterViewer has practically no interaction with font information.
  It is not possible to give CharacterViewer a font and ask it to display all the available
characters in that font. CharacterViewer can only display all characters (without consideration
of any font) in their order according to Unicode (and a few other encodings, but I'm interested in fonts not encodings). Also, when CharacterViewer displays the font variants of a given character it only
displays the shapes and not the font names. The user has to click each shape drawing
individually to see what is the name of the font it corresponds to. The older interface
which automatically displayed the font name next to the glyph was much simpler and
user-friendly.

I found those now-disappeared features incredibly useful as I wrote articles on ancient texts
involving many unusual characters. 
  Is there any reasonable chance to restore those features on a Yosemite system ?

UPDATE 18:16 : In answer to a comment below, here is a sample of characters that I often use :



Note that my problem cannot be solved by simply gathering "all the characters I need" in the favorites Section of CharacterViewer. To exaggerate slightly, every epigraph has its own characters and I need to update my set of characters periodically. The typical character I need is often in the "Private Area" of the Unicode standard. The most comprehensive font I found so far is ALPHABETUM, and with the old Character Palette I regularly discovered new characters from ALPHABETUM.
The problem you mention has existed since OS X 10.7 was released nearly 4 years ago, so it has been discussed a lot in various places.  I think the best fix is probably to use the 3rd party alternative palette, Ultra Character Map.

https://itunes.apple.com/us/app/ultra-character-map/id520265986?mt=12

However if I remember right it cannot handle glyphs with no unicode codepoint assigned (i.e glyph variants).