I do not know if I fully understand your goal but zswap-arm only uses a space in RAM and does not use the disk at all. All data that is put in the RAM swap space is also compressed which allows more data to be put in to it. If a drive is used for a swap space it likely will take more of a performance hit with the read / writes.
Since you are posting here I am assuming you are running your pi3b on 64bit and if you intend to use it as a desktop it's brain power is barely there to work. I have tested my pi3b with zswap-arm using say firefox and it does work ok but the waiting for pages to load up because of the low brain power of the cpu is some what of a draw back. But after that it does play youtube vids.
With no swap using firefox Your system will eventually will freeze. With swapping to disk things get sluggish and mouse freezes until things get caught up. With zswap-arm things are a whole lot better responsive.
If you have proper cooling for your pi3b board if it was me I would look into overclocking. It seems that all pi's are not created equal when it comes to overclocking. One guy's config may or may not work on yours. The main thing is to get it to boot and maintain a good cpu temp using cpu-temp-speed to monitor. On the pi3 when I was using it as my main pi board I would put in the config.txt a line that would cut back the cpu when it hit a certain temp just below what the RPi people use as default for the pi3b as a safety valve:
I am not bashing the pi3b at all and when it was on the top of the RPi food chain I thought I was on top of the world with it. I even remember using the pi1 when it was their latest as slow as it was I was very happy with it.