How to develop a Reflective Habit BEFORE moving

Five relevant questions and suggestions:

1. Do others share the same experience

I think personalizing a "blunder" with any other name (non-reflecting?) doesn't change what it is ... which is basically a blunder! It is a stretch to assume that if you perform some "reflect"-ing ritual, you will automatically not make blunders.  You will probably not hang pieces and pawns if your trained board vision is decent ... but anything beyond that is a measure of your other chess skills.  Your skill at chess is a gigantic toolbox with a mix of useful and defective wrenches, hammers and screwdrivers.  We make blunders of a quantity + quality that is reflective of where we are at chess (knowledge, experience, discipline + will) , not simply due to our lack of focus/attention. Whenever I hear  somebody say "I need to change my thought process / behavior to make less blunders",  there's usually a ton of other skeletons in that closet beyond just "focus" or "patience" :)

2. More important, what habits can people share in the shorter formats to avoid blunders; e.g. count to 10?

 Consult NM Dan Heisman's "Two Move triggers" novice nook for some fundamental "eye opening" lessons about time management.  There is no simple "count to 10" approach though some coaches have often asked kids to sit on their hands so that they won't rush into moves.  Getting better at tactics (not just playing winning shots but recognizing en prise-errors and visualization mistakes) also helps. Another series of articles to go after are Steinitz's rules (The Exeter chess website is a good reference) which explain in "mathematical/game theory" terms how people really "lose" at chess (or any turned-based game).

3. I  intend to try "count to 10", and assuming 30 moves, this suggests 30x10 seconds or 300 seconds (5 minutes). 

What you do in those 10 seconds may actually take 1-second or even 1 minute ... it really depends on the criticality of the position so it is dangerous to hand-wave some magic rule over it.  Some positions need more time, some less depending on how analytical (how many forcing moves require concrete calculation? etc.) If you watched strong players (Masters etc.) play 5-0 blitz, even they will often slam their brakes and take up to 30 seconds in really critical positions and make up for the lost time elsewhere with varied success. These calculation-monsters actually make a "risk vs. reward" decision to invest this kind of time because the entire game might be on a razor's edge at that position... Sure, it takes experience + skill to be able to manage one's time under pressure and decide when to search for a best move and when finding something good enough is more than sufficient.

4. Do not play shorter forms of chess when tired or distracted - use common sense

I would not play chess in general if I'm distracted  however tempting that it might be ... if that were so easy  *sigh* :)

5. What do people feel are the benefits of the shorter forms of chess? A sharper tactical vision?

I think all one can be possibly doing with blitz is a combination of having fun +  practicing/trying out openings + winning/drawing technique or simply exercising and maintaining your tactics muscle + stopping it from atrophy/getting rusty. You are not going to get better at tactics by playing mindless blitz sessions for hours and hours. That is just silly. Look up articles on Deliberate Practice vs. Mindless Practice.  Mindful blitz practice takes a lot more effort (looking up the game you played, the opening choices, focussing on your blind spots and mistakes you made and actually recording them and trying to focus on eliminating those exact mistakes in your next game etc.)  I would argue that mindless blitz playing actually reinforces (makes worse) the terrible habits/errors in visualization  the same way an impatient + early-intermediate piano student often tries to rush through a piece that he cannot sight-read to play 10 clean notes in a row.  You are effectively practicing to get worse and cement your bad habits... and I speak from personal experience as this  HIGHLY underrated impatience/emotional/discipline problem is one of the many reasons I've just stopped getting better at chess  :)

In my experience, some players are very aggressive with their pieces in the shorter forms of chess. Others - I notice the higher ranked - just seem to play a good and solid game of chess.

The stronger they get, the more opportunistic and more solid their move selections tend to be ... also,  you only see relatively few "killer" moments of tactics on their board but if you look closer, you will see a ton of defensive/blunder-preventing moves that were played by both players that on the surface look like boring moves to an untrained eye.  This kind of playing took a lot of conditioning, discipline and "deliberate" practice to get to ... not just some "thought process" light bulb that just turned on ... though that is just one place to start building a foundation to playing cleaner + safer chess.

I think one simple idea to improve your experience at faster games (which I know you'll want to go back and keep playing because it is fun :) ) is to play with an increment/delay of say 5 seconds?  This simple change to your time-control can  DRAMATICALLY change the way you respect yours + your opponent's moves some more as there is less scope for  random-garbage moves to force your opponent's clock to flag.  I've noticed that this helps me on days when I seem to be more erratic/emotional/impatient than others and helps me focus better / punishes my bad habits much worse. :)