FIRSTLY, I'll start this post off with something I noticed needs to be fixed.
The Pact cycle cards that were reprinted in Modern Masters 2013 are considered colorless despite the spells having color declared on the card.
SECONDLY, especially for Commander but even for other formats like Legacy and Cube, I would request a "Color Identity" feature be added to the list of quick sortables next to Mana, Type and Set.
For commander this allows anyone to double check that none of the cards in their deck accidentally conflicts with their color identity
For cube this allows anyone to
balance their color wedge of spells in mono color and multi color (if you have a card with an ability of a different color it's a multicolor card)
For legacy (and other 60 card constructed formats) this allows anyone to see what kind of mana requirements and fixing they need to support to utilize all of their deck's power and
balance out how much of a weight it becomes when going into uncharted deckbuilding waters.
THIRDLY, sorting by colors should always go in the order of WUBRG and would be preferred to happen automatically as a standard sort upon clicking the "Analyze" button and while using the "hot" sorting headers of Type, Mana, etc.
As a MTG player/deckbuilder and a Software Developer, these are things that I would like to see implemented for consistency as well as utility in the flow of the DeckStats webapp for the benefit of every user.
The order for sorting multicolor identity should go combinatorially with White holding the most weight, then Blue, and so on in the order of WUBRG.
Example is as follows:
WU
WB
WR
WG
UB
UR
UG
BR
BG
RG
WUB
WUR
WUG
WBR
WBG
WRG
UBR
UBG
URG
BRG
WUBR
WUBG
WURG
WBRG
UBRG
WUBRG