nginx is way faster than apache and same or better than openlitespeed
plus openlite speed is more tricky to set up, implementation for aapanel is still beta so may crash
if you want a wordpress site faster by experience I would say either use nginx in aapanel and then go to appstore-->php_version-->settings--.>configuration-->Memory limit --> usually is 128mb or lower
but if you increase it (depends on hw much ram you have, I have 8gb so I pump it up to 1024mb or if I go crazy 2048mb but in general keep it always even when you go crazy, at a quarter of your total ram) it wil give you a massive boost in wordpress
at least for me it was but if you increase it too much (80% of you total ram) and get much traffic it will eat you ram pretty quick and cause problems
openlitespeed is fast but nginx with the right settings can even surpass it,
the only deference is openlitespeed it lighter than Nginx
take a look Nginx vs openlitespeed
in aaPanel
https://forum.aapanel.com/d/1200-aapanel-nginx-vs-aapanel-openlitespeed-performance-results
More technical comparison (not in aapanel)
https://conetix.com.au/blog/apache-vs-nginx-vs-openlitespeed-part-1/
by experience my advice
just research on tips and trick (settings to speed up your wordpress site) instead of switching to openlitespeed
give it some time when is more mature give it a try