I would not go to far lengths.
I won't buy a lighter bike. I love my bikes and they are not the lightest, though not the heaviest. I have no interest in buying a lighter bike and definitely don't want to buy one that will save me 15 seconds over 100km at 40kph.
I probably won't buy lighter deeper wheels. Wheel weight is largely...meh when it comes to importance for me. My wheels also aren't heavy as it is and my road bikes are rim brake. All that adds up to deep carbon not being ideal for me. I said probably won't because I do think about it. Can't bring myself to spend $1k +/- for some wheels though. I don't think they would transform my experience and I don't think the gains would be worth the cost.
I for sure won't buy more aero clothing. That will just make me feel and look like a stuffed sausage. Why would I pay for that? My current cycling clothes aren't exactly parachutes.
What I would do is what I will do this winter- zwift and weight train. I was noticeably faster when I was 10# lighter. It wasn't so much the weight as a combo of weight plus strength and stamina that came from simply being in better shape.
So I'll do that this winter.
I can't out exercise my diet, but I am going to die trying!