In the end, will opt for the 128GB Quest 3 to gain an IPD adjustment wheel. Mine is 65.5mm, in between settings 2 (63) and 3 (68) on the Quest 2. Some users say it is "fine" or "good" using an IPD +/- 2mm, but some also report headaches and eye strain over a period of time. Whilst the low price is enticing, a lack of exact IPD adjustment is a dealbreaker, especially as I expect to get years out of the device. My eyesight is already not stellar to being with.
I've got the same IPD as you actually and I use the 3rd setting (68) on my Quest 2. If I get eyestrain it's becuase I forget to lower the brightness since it's quite high by dafault. A VR headset with brightness too high is like staring into a flashlight, same goes with a PC monitor to be honest in my case.
Anyway, like Walle12 said, most people fall in between the 3 settings. I haven't heard of this being an issue among the large amount of Quest 2 users.
Not buying it due to a lack of an exact IPD adjustment is a bit surprising considering all the positives talked about earlier, the discounted price aswell. I have tried the Quest 3 and I wasn't able to notice a difference when the distance was matched perfectly.
The fact that your eyesight isn't the best as you put it, makes you notice these issues less and not more, compared to someone who has superb vision in many cases. Also, VR can take a toll on everyone in general, just the way it is. Stare into any screen and you will tire over time, there is more then one factor that can give discomfort.
I understand your hesitation, but I also think you are digging into this a bit too much. If this is your first plunge into VR you will be amazed at what it can do. When you put on a good headset, player and whatever 8K vid you like, you will be blown away.
