Q&A: Cushion Cut for $6-7K Budget

First off, I want to say thank you for creating this website. It is truly awesome!!

I am interested in a cushion cut diamond in a halo setting. I want the finished product to look like a photo uploaded to your site’s ring gallery (link below).
https://www.diamonds.pro/ring-gallery/cushion-cut-diamond-with-halo-setting/

My budget is approximately $8K total. Assuming $2500 for the setting, this leaves about $6-7K for the diamond.
Please let me know if you can help with the following questions:

1) Do you have a recommendation for the carat size?
I am concerned that the ring may look awkward if the center stone is too small (i.e. the side stones will take away from the center stone which should be the ring’s focus). My g/f is also petite (100 lbs, 5’2 and small hands) and someone told me that a big carat size may look ridiculous on her hand. Bottom line is I don’t want to buy a diamond too small or too big and appreciate your thoughts.

2) Do you agree with the following cushion cut parameters based on the ring I am looking to replicate?

Color: D through G
Depth: Under 70%
Table: Under 70%
Fluorescence: None to Faint
Lab: GIA

3) Do you have any suggestions for the following cushion cut parameters based on the ring I am looking to replicate?
Length / Width ratio
Clarity – I get that SI2 may be clean to the naked eye, but your site said be cautious with the open table of cushion cuts.

4) Do you know if the client you assisted in the ring I am looking to replicate used James Allen for the setting?
I ask b/c I have contacted James Allen and they told me they can put a cushion cut halo on the setting below. I am trying to gain more comfort that it will come out the way I want it to look.
https://www.jamesallen.com/Engagement-Rings/James-Allen-exclusive/18k-White-Gold-0.29ctw-Halo-Pave-Set-Diamond-Engagement-Ring-item-7941?a_aid=dmnd1357

5) Is my budget realistic here? If so, do you have any suggestions for some cushion cuts within the parameters discussed above.

I have no problem dropping to an H color and the stone you picked out looks very nice.

I notice a small (very small) blemish on the table (just off the center of the stone). I only see it when the diamond spins around. It is really small, but for some reason my eye is now drawn to it after I noticed it. Two questions here:
1) Is the spinning diamond magnified or is this real eye view?
2) Is this too small to worry about?

Thank you Mike. That is what I suspected, but wanted to be sure. Unfortunately, the diamond you recommended is no longer available – I contacted James Allen and the seller removed it from the site. Would you mind recommending another?

Thank you Mike! I purchased through JamesAllen last Thursday and expect the ring in about 2 weeks.

Customer service was excellent and I told them I was referred by your site.