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TL/DR: Get the m3/1m control arms, refresh your old bushings, replace your diff bushings. Your budget isn't big enough to get new dampeners on top of the above, but you could always replace those later if you can't swing them now?
Long rambling explanation:
m3/1m arms don't increase NVH much, but they certainly will a tiny bit. My 1st car was an e30 325ix and I needed a car in my life that could handle somewhat similar to that, but I was wanting a bit more on the track day setup bias as it is my fun car. So... I modified my 135i.
In my 135i got the m3/1m arms with turner monoball bushings in the front (basically making them free of any deflection), replaced every suspension bushing to polyurethane other than the rubber bushings included on the rear m3/1m control arms, powerflex black subframe bushings, powerflex purple diff bushings, I have a strut tower brace front and rear, standard OEM sport suspension, and eibach sway bars front and rear. My overall chassis and suspension is much stiffer than from factory as a result. I value the engaging drive and was frustrated to no end in the lack of precise "tossability" (while autocrossing) that my e30 was so good at.
I wouldn't want this as a daily driver because of the noise... of my nearly straight piped exhaust and catless downpipes. The road noise doesn't bother me as it isn't much of a difference for the returns I get in handling. If you do lots of road trips or 75mph commuting, that's where my turner monoballs would bother me, but I doubt that the more solid RUBBER in the standard m3/1m bushings would be anywhere near as the zero deflection in my monoballs. If my NVH is only slightly higher than what most people would want, I'd say it's a home run if you get the standard m3/1m arms. One of the bigger downsides that nobody mentions is actually how the negative camber sniffs out uneven road surfaces. You have to pay attention to where you're going much more because your car may want to follow the undulations in the road more where heavy traffic wears ruts into the road.
You won't have rubbing issues with 235/40's once you get the negative camber up front from the m3 arms. Apex has a very extensive fitment guide on their website you should check out to prove so.
If you have the fluid filled OEM diff bushings, you may want to look into getting that floppy garbage swapped out with something stiffer to finally plant your rear end, especially if you're at 100k+ miles. The limited traction under power and the e-diff makes your diff flop around a lot when powering out of a corner.
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