I’ve used PDFill and eventually get done what I need to. I find it kind of hard to use but in fairness I only use it once a year on some Tax forms so have not tried to learn it.
They also have some free PDF Tools that are useful for things like merging or extracting pages.
My favourite is Sejda PDF Desktop. The free version is limited to a certain number of operations per day. Around tax time I buy a one-week license for $7.95 https://www.sejda.com/desktop
I use PDFElement but I am hesitant to recommend it. The recent upgrade from version 7 to version 8 did fix some major problems but also removed features people had come to rely on. Also, I bought version 7 with a “Lifetime” license but then they said that lifetime referred only to version 7 and I had to pay for the upgrade to version 8. This wasn’t a big deal but it was a bait-and-switch situation and soured me on the company (a Chinese company, BTW).