I did LAS in June this year, took 1K outbound and 1A return.

It seems common to note that 1A/K are quite noisy, obviously they are by the forward galley and lockers, but I didn't find it problematic at all. I suspect a lot depends on what you are trying to do onboard - if you're trying to work you would probably find it a lot more intrusive than if you've got headphones on watching a film, or good earbuds in and snoozing contently....

I was lucky in that I had an excellent crew both ways, particularly outbound. They locked out the front toilet during meal service as they are required to do, but unlike some reports, allowed access at all other times. The proximity to the galley was advantageous if anything, meaning I could be served first and have stuff cleared away, while it was easy for the attentive crew member just to pop out from the galley and see if I needed anything.

Like yourself, I was considering the mini-cabin as the alternative, I recall the proximity to the WTP bassinets being a factor in my thinking, but I've no doubt I would have been content there as well, so I wouldn't suggest moving - just offering up another perspective

Per Geordie405 they did hold back the mini cabin on arrival until the main cabin had disembarked in my case.