Hello, and welcome.
First, some bona fides, such as they are. I’m graded as a three stripe white belt at a BJJ school that emphasized sport and I have about twice the mat time with my current instructor, mostly in small groups or one-on-one at his home mats. Belts have never come up, so I remain graded as a three-stripe white belt. He is a four-stripe brown belt at a BJJ school that prioritizes unarmed combat. The black belts there are almost all accomplished competitors as well.
I also spent a few years bouncing part time where I’ve had success, such as it can be measured. Nobody ever whooped my ass and I never had to stand in front of a judge to explain my actions at work.
I got 500/350/615 lifetime natty strong at about 270lbs prior to beginning BJJ in my late 30’s, so I can’t comment on how best to strength train while also getting your mat time in. Your strength goals seem very reasonable to me, especially if you’re following a Wendler methodology. I mostly ran pretty standard 5/3/1 over the years, doing very little aside from getting stronger and shedding fat.
Being strong is great, don’t get me wrong, especially when the disparity gets significant. Your mat time is still where you’ll get the most benefit. It is here where I’d encourage you to look closely at your training priorities and school selection, if you have such options. In simple terms, if you find yourself suspecting that what you’re learning may be useless in a fight, is probably is. Don’t waste time training sport-only stuff in your rolls, either.
I’ll be the first to admit that I don’t have a good answer for someone’s shin-to-shin butt-scooting x-guard entry, but that was never a priority of mine. Luckily that situation has yet to materialize off of the mats for me.
Can you arm-drag a chump to take his back on your feet? Great. Now catch blue belts with it too and choke the shit out of them, so they might better understand their folly.
Can you get to a clinch with a chump who might be swinging on you? Great. Now get to the same position with blue belts and go to work.
Can you put that chump on the ground reliably? Great. Now get it to work on blue belts.
Can you advance to mount and hold mount? Great. Now get it to work on blue belts.
Can you maintain a floating pin with knee on belly? Great. Now get it to work on blue belts.
Can you get out of the guard and back to your feet or advance to a dominant position? Great. Now get it to work on blue belts.
See where I’m going with this? The basics are the basics for good reason. You don’t need to resort to elaborate grappling when the adrenaline kicks in and you start running the algorithm you’ve created with your mat time. As my instructor says, try the front door first. It is open more often than not.
Don’t play the weight class game, either. Seek out a goon of a training partner like me and get to work.
Good luck with your training and with your work!