I have a character idea but frankly I'm at a loss to implement it. Are there any good ways to significantly increase caster level or otherwise meaningfully boost the effectiveness of Dispel Magic? I'm not aware of anything besides the orange prism ioun stone. Any help would be greatly appreciated.
In practice I've found counter-spelling to be mostly useless, however dispelling is a go-to mid-to-high level combat action.
There are the feats Dispel focus and Dispel Focus Greater from the Monster Summoner's Handbook. Each add +2 to the dispel Check. Could not find a reliable link.
The trait gifted adept gives +1 CL to one spell.
The feat Varisian tattoo/Mage's tattoo gives +1 CL to one school of magic. Though Spell focus Abjuration isn't the greatest feat.
Putting the Orange Prism in a wayfinder also gives an additional +0-+2 CL Bonus.
Alchemical Components are another big one. Cold Iron nets you +1 to CL for abjurations.
Magic Item Altar of Nethys adds +1 CL to one spell.
If you're a divine caster Bead of Karma Gets you +4 CL for 10 minutes/day.
The Feat Spell Specialization adds +2 CL assuming you have spell focus abjuration.
Down the line the feat Spell Perfection increases the bonus to CL from other feats, such as spell specialization and Mage's tattoo.
Various other class features, such as the Arcanist's arcane reservoir (further modified with the potent magic exploit) can also increase Caster Level.
Teamwork Feat Allied Spellcaster gets a +1 CL but the conditions for using it are circumstantial.
There are quite a few feats that tack on additional effects after successfully dispelling, but I've personally yet to put them to use in any regularly meaningful way.