What happens if an MMG doesn't have a wall directly behind it?

Just acquired new MMGs today. Sold my last set of maggies (3.6s) in 2007.

The rectangular room I am in (13’ x 22’ x 9’) has some challenges. One of the 13 foot walls is a slider to a balcony with plastic vertical blinds. The other 13’ wall has a hallway in the left corner (43" wide) and a huge cutout to the kitchen above 44" (69" wide by 48" tall). Floors are laminate with a 6’ x 9’ area rug just in front of the speakers. Walls are currently untreated.

My listening position is in the corner opposite the hallway near the slider.

The MMGs are currently positioned on the wall with the hallway and cutout, 39" off the side and back walls. Tweeters are to the outside to broaden the sound stage.

Right now, the amp and other gear are on a horizontal bookcase in front of the cutout. I will be able to clear some furniture out to bring the speakers further into the room as necessary and can move the amp and other gear to the 22’ side wall.

Could the MMGs be positioned off the 22’ side wall or will the right speaker be dominant given my listening position?

As expected with new MMGs, they are currently very bright and should mellow as they break in. I am open to suggestions to warm the sound. Was planning on adding Anti-Cables to the speakers, but am concerned they will add to the brightness.

What other under $1000 speakers could provide the detail and sound stage of maggies and better deal with the uniqueness of the room? I have listened to the .7s in the local store, but am not sure if they are sufficiently better to justify the $1400 price.

Longer term plans include adding a digital library running off my PC into a wireless DAC.

My system is:

Adcom GTP-500 and GFA-555 (checked out and functioning as designed)
Onix XCD-88 CD player
MMGs

Musical preferences are folk, bluegrass, jazz, classical and rock and roll (60s and 70s) and female vocals.

Thanks in advance for any help you can provide.