Hey, just quickly: thanks for claryfying some things!
1.5 is one percent: 150/100 which was your assumed initial weight (145 now then, hence 1.45). So how much percent is 28 out of 150: 28/(150/100) => 28/1.5
127 initial lean mass is really crazy good if true

Of course, I mentioned the problem with the measuring devices, right. Anyway, what does the scanner says now?* If the scanner was right, you would have "almost" visible abs (pretty much all sixpack) with around 12.5% of body fat ( 18/1.45 ), now, my conservative estimate is still that the scanner undermeasures the body fat, your lean mass might have been rather around 122 and thus the body fat more conservative for a lean untrained person. You will still most likely be approaching 20% by now slowly, which could be a sign to do a change.
*Edit: sorry, I didn't the notice the beginning of your message at all where you actually mentioned it, I saw only the quotes (the forum scrolled me wrong to your message), I will post one more reply
The ratio... you cannot optimize it much. When you are beginner, it's better. When you are advanced, it's worse and worse, although with lots of effort, it should never be worse than 50:50, but with suboptimal effort and bad eating, it can be 40:60 even if you a beginner. Genetics is also a variable. The only things that you can optimize (that can determine whether you're approaching at least those 60:40 ... and perhaps 70:30 is even very rare for good disciplined lifters) is: diet + rest + optimal training... things as usual. If you have good training and bad diet... or good training, diet and subpar rest - all of that will make it worse. The good ratio, the lean muscle is a reward for the best possible physical lifestyle you can lead, pretty much.
How to determine a novice or a beginner (e.g. why I am, was until recently a beginner after 4 years of doing fitness): that is pretty much determined on how much you have taken already from the "newbie gains". Let's say (I will be optimistic) that if an average male has a potential to naturally gain +25 kilograms in his whole life of LEAN MASS, then the initial 10-15kg should be moderately fast (let's say perhaps even within the first 2-3 years of REALLY good training/eating/rest + proper bulk-cut protocol) and that would be the "beginner's gains" (in my mind). Then, once you pass that mark, everything will so ridiculously slow down (=I haven't passed that mark yet, I gained around +10 KG of lean mass since my assumed initial state) that you will soon forget how easy it was on the beginning. It will soon become like +2 pounds of lean mass a year after one or two cycles of bulk&cut and everything done optimally. That is also why many ambitious guys throw their brain out, forget their future, health and everything and start doing PEDs, because - if they are already able to do everything right, PEDs will restart for them that period of "fast growth" they remember from their first years and everything will be "rainbow-awesome" again
So, in short, FFMI will be a determiner in some relative sense of whether you are a novice or not.
I don't do hip thrusts. Currently my really-high-rep bulgarian split squat session once a week (with an additional 30-35kg of weight) is both an insane cardio and a booty-builder ;p (insanely really|) 4 sets of 20-30 reps (cardio is usually the biggest limiting factor there: it's quite an achievement to perform it at all). But, I don't say I will never do hip thrusts... maybe I will

Who knows what my 1RM on hip thrust could be atm. ;P (albeit the brain's not used to the movement)
But a 250lbs on a compound lift is really really good! I have no such number anywhere. (It is may be true that hip thrusts will offer the shortest ROM from the compounds lifts, but still, pretty good!)
But anyway, my compound lifts:
- With one exception, I don't know my one rep max (1RM), since I mostly don't consider it as good way to train or safe for me in any way, so I will make some assumptions.
-
deadlift: 82.5 kg for 4-5 sets of usually 8 reps (but I wouldn't say it's to failure, I try to avoid deadlifts to failure as much as I can, if anything starts to fail
sometimes, it may be the grip, but that's all); I suppose my one rep max would be at least 100 kg if not slightly more.
-
squat: (=rocked over to my back from the ground, which itself is a compound lift like hell

) 82.5 kg 4-5 sets usually 10 reps, in no way to failure. One rep max probably also 100 kg...
-
bench press: well, I didn't do bench press throughout my bulk at all due to various reasons I mentioned earlier I don't want to repeat. But I restarted it and plan on doing it regularly from now on. I do a kind of "pin press" where the bar first rests pretty much in the height of my chest for a moment before I press (=zero stretch reflex/zero momentum) which is a bit harder, there for reps I do currently 56kg, 4 sets for 8 usually to failure. But I
tried my one rep max actually two weeks ago or so, because I was curious how weaker I became after not doing it for so long, luckily enough it was the same as what I managed to do about 6 months ago,
80kg 1RM on bench press (=pressed from pretty much the chest height, from the bar at total rest)
-
overhead pres - 42 kg, around 4 sets, 6-8 reps to failure
- pull ups / chin ups / commando pull ups: usually I make around 5 reps in a set regardless whether I have 0, 5 or 10 kilograms of added weight on myself

(=after sufficiently rested and regenerated), 4 or more sets. Althought with 0kg I assume I would do more reps than 5 in a set now: the last time I tried it was the next day after forearm training, which was limiting me and right after deadlifts that hit lats too, so that's why even 0 kg felt similarly difficult as otherwise with plates.