I'd suggest posting this over in the Strength Sports section, as you'll be likely to get better targeted advice over there. However, my 2 cents is this:
1) I'd set shorter term goals of 500 squat and 600 dl. You'll get to 600 and 700 eventually but make your intermediate goals smaller.
2) Box squats are individual. The PLer I train with doesn't believe in using box squats unless depth or form is an issue... neither does Al Caslow, one of the world's top 165'ers. Some people love them some don't. My advice is to experiment--the only way to know for sure is to try different things for a period of time. What gets you to 600 may not be what you need to get from 6 to 700 or 800.
Besides, pushing the upper echelons of strength is largely individual and there is much less solid advice than in the lower echelons. Experimentation is flat-out necessary. Box squats on speed day are fine IMO. Change it up. See if you feel a better result going from ME box squats to your free squats or if they make better sense solely as a speed day thing.
I used to box squat exclusively for years, and now I'm not using a box at all for any day. It's all different. "Doing free squats is a great way to grease the groove of...free competitive squatting." Al Caslow
3) Be ready for the long haul. This is definitely a long term game and often times progress can be slow and frustrating. Sometimes it comes easy sometimes not. This is precisely the reason why experimentation is necessary--lifter's weaknesses and needs vary widely.
4) I would really invest in a couple sets of chains. You don't need them per se, but you're getting to the point where they'd be really helpful, as would bands. I think chains are better for some purposes, bands better for others.
5) purpose of Speed day is Speed. Bands help because you don't have the braking effect at the top of your lift, but chains do this as well. Chains I think are slightly less goofy to use, and for that reason I would suggest using them first/more often than bands. It's hard to explain, but with bands there's sort of a "grounding" effect that you don't see with chains--bands self-stabilize you into one certain groove, whereas chains wobble and help your balance to stay "natural".
I don't remember who it was, but one of the big boys on EliteFTS was explaining this when he said he doesn't use much band work anymore because he was having trouble with balance.
Regardless, they're both useful. I would say use chains more often though.
6) If you're seeing progress from the Westside template, then stay with it. If it ain't broke don't fix it.