If you want to use a generic type measurement then the waist to height or waist to hip ratios are arguably better than BMI.
I would also caution chasing just scale drops. As an estimate, once you start your weight loss journey you should try not lose more than 1% of your body weight each week.
The goal is to hold onto a bit of muscle whilst your fat drops, this has a few benefits
keeping muscle helps you burn more calories, so rather than lose muscle and fat, you would want to try keep a bit of muscle so that you burn more and dont have to reduce your calories continuously every week.
This also helps reduce rebound where maintenance calories are so low that once someone reaches their goal weight they start eating a bit more and dont realise this is way above maintenance.