Hi Leo,
Whether the head you're after is for photography, videography or for a scope, I'd much prefer a "fluid" video pan tilt head to a ball head. There's far more control and usually much better load capacity. the only thing you have to be sure of is whether the head can tilt up to the zenith. On my Manfrotto 501 video head it will do about a 70° tilt upward, but if you reverse the mounting it will get to 90° (zenith).
If you go for such a fluid head (and there are Chinese copies of such) see if you can try before you buy as smoothness of motion is important in helping with tiny adjustments and also check for range of motion in reaching the zenith. You also need to decide, but looks like you already have, on Manfrotto versus Arca Swiss compatible heads.
I suspect something like this would be OK, but this uses a Manfrotto compatible plate. I'm sure you'd find similar with Arca Swiss compatibility. Whatever you do ... Don't buy a dinky little head of either type. Remember try before you buy.
https://www.ebay.com.au/itm/27643632...Bk9SR-qSjLfmYw
Best
JA