I'm not sure if any of the experience I have had with my wife who is also 52 will compare to your own experience with your history. As a female that has been into body building for a while I think it is safe to assume your diet is on point and your workout routine is as well.
Also I have noticed the trend for larger muscle masses on women being the trend currently and my wife's goals don't go that far. Now I can tell you what we have tried and hopefully you can add that to your own knowledge and come up with something better than you currently do.
My wife has done Anavar as well and she has went up to 15 mg a day, but she broke it into three 5 mg doses taken at approximately 8 hour intervals and with this she saw tremendous strength gains, but it did not help as much with weight loss. If your really lean already and were going to do a bulk I would definitely look at slowly increasing your Anavar intake and figure out how high you can go before the sides kick in. I have heard of some women going up to 50 mg a day without issues for short cycles, but genetics will play a huge role in that.
Now she seems to tighten up a little while doing Primo injections, still the scale doesn't move any faster when dieting, but she does seem to get firmer and muscles start to show better. She does 75 mg of primo, but started at 25 mg of primo a week and worked up to that 75 mg. She says she might try 100 mg on her next cycle. Now I will caution that Primo puts her sex drive in overdrive just as a cautionary note. Also know this would be an intra muscular injection, so if your not good with pins might not be the way to go.
She tried Clenbuteral for weight loss, but it gave her a constant headache. That is just her, because I use it and for me the sides are night sweats and cramping when the dose gets above my tolerance level.
Last but not least is she has also done 20 mg per week of testosterone injected subcutaneously. By itself it just gave her more energy, but when taken with Anavar it was like a multiplier with the strength gains, but she noticed a little bit of hair growth on chin and stopped that, but she says she may try 10 mg later and then just have the hair waxed off.
I hope some of this can help you achieve your goals. As a note I am not a doctor and honestly I am learning about the compounds as I can through internet research and well real world experience. Anything you would like to share I am sure I would also find helpful.
Last note is SARMs or peptides might be the way to go. I just don't trust things that really do not have a lot of official human trials if any on them that I am putting into my wife's body.