I did know about mirroring before making this layout. For some reason, it just didn't come so naturally to me as I would expect it to. I don't really like using a thumb modifier key either, as hand alternation is a frequent thing in colemak, I find it tiresome. I never learned to touch type on QWERTY (and frankly I hate using the layout), so mirrored QWERTY is out of the question for me.

No, the hand alternation in colemak is nice. I'm just saying it makes it more difficult to type on mirrored colemak cause of all the modifier pressing you have to do.

Huge update to STREAK!

Instead of going off of intuition, this time I did my research, looked through corpus data, and I've made a much more efficient layout. You could call this one STREAQ.

Things I had in mind when revising the layout:

1. Reading through an old article, I realized that Dvorak's original one handed layouts didn't follow the conventional row-by-row finger stroke map, like it appeared in my last layout—the problem with that was that original typewriters that Dvorak's layout was intended to work with had a different degree of stagger than conventional computer keyboards, so it didn't work well in this aspect. I decided to make my own system, which you see in the image above. Blended colors mean that the key can be stroked with either finger. K can be stroked with either the ring or pinky, G can be stroked with either the middle or ring, and N, B or O can be stroked with either the index or middle finger. This makes certain combinations much easier to stroke, such as the ending "-tion", which is stroked by the ring, index, middle, then index again.
2. I wanted to avoid common single finger letter combinations as much as possible. This meant placing consonants most unused with vowels at the right hand side of the keyboard. Q was moved to the index finger cluster because it doesn't usually come before any of the vowels stroked by the index finger. B was moved to the index finger cluster in place of P, so that P could be stroked with a vowel without hurdling past a single row with one finger. Another reason I moved B there was so a common word, "by", could be stroked without successive pinky strokes. B is a much less common letter, and in cases where it does come stroked with a vowel (like the word "be"), it can be stroked with the middle finger, leaving the index finger to stroke any vowel in succession.
3. D is placed to the bottom left of the S key, instead of to the immediate left. This should reduce leftward horizontal stretching of the left hand, which is awkward.
4. Instead of keeping the ZXCV cluster, this time I tried to make the layout as efficient as possible, so it needed to go.
5. I wanted to make "CK" easy to type, since this is a very common digraph for both letters. This is the reason I placed K at the right of the keyboard in my original layout. The problem is that the letters themselves are not very common. The solution above is what I decided on, keeping the keys to relatively comfortable comfortable roll while not having them displace key positions that would be reserved for more common letters.
6. Originally, P was going to be put in place of K, so that the "SP" digraph could be comfortably typed. However, I found out through corpus data that the potential digraph with the ring finger and pinky that could result if K was placed there (CK, KY, SK, and their reverses) outweigh the digraphs that would result if P was placed there (SP, PY, and their reverses). I had to make a sacrifice that meant typing the common digraph SP would be a little awkward, with a hurdle. Moving P to another position outside of the pinky cluster would either relegate a more common letter to a position disproportionately hard to reach, or screw up its rolls.
7. F's position was moved to a position easier to type. This was much needed, as F is more common than P (although only by half a percentage point), the key position where it used to be. I thought about placing it where W was, but I realized it would make typing common words with F like "for", "after", "first", and "if" require a hurdle or successive single finger stroke.

Some things I feel iffy about, that I wasnt able to address:
1. The digraph "RL" and "RN", which requires a middle finger hurdle and successive single finger stroke respectively.
2. Letter combination "TU", "MU" and their reverses, which requires a successive single finger stroke of the ring finger.
3. Digraphs "PY", "FY", "DY", "CY" and "SY", which require a successive single finger stroke of the pinky finger.
4. Dipthongs "EA", "IE", "IA", and their reverses, although successive single finger strokes are much easier if it's the index finger.
5. How hard the apostrophe key is to reach.

Here is a download to the layout (MEGA)

I welcome you to suggest changes I should make to the layout, or try revising it yourself.