Upon giving up on liquid, I tried tightlining with gel. Not great at first because I had the wrong brush. I used Bobbi Brown's Ultra Fine Eyeliner Brush which is fine for over-lash lining with powder liner, but ridiculous for gel. It just leaves a faint, too-thick, unevenly pigmented mess. The holy grail for eyeliner brushes, particularly for gel liner that you're stamping under the lashes, is Laura Mercier's Flat Eye Liner brush.
No joke, this thing changed my life, importantly, and probably forever. So now, after applying a base cream shadow or tinted primer I do a pencil line above my lashes in dark brown or black. My current pencils in both colors is MUFE aqua eyes because I like how easily it glides on and the color choices are amazing. But I'm not married to these pencils. I think I'm going to try Dior next. Then I do a tightline to my top lid in bobbi brown's gel liner in black with Laura Mercier's Magical Perfection Liner Brush (same one as above, I just renamed it). The BB gel is the only one I've tried. Because why mess with a good thing? It's a long-wear formula, it goes on easy, has a super-pigmented inky black and as long as you just make a line and don't spread it on like margarine on toast it will not stamp down onto the lower lids. I've tried the margarine approach and it does transfer a little, but very little. It actually is a good technique if you want a very subtle smudge of color along the bottom water line.
It only takes a minute for the whole procedure because both products are easy to apply. And the effect is really dramatic...and yet natural. It looks like your lashes go on forever and really defines the eyes without looking like an art project close up. When I want to look super sexy I add a stripe of a Laura Mercier caviar stick basically right on top of my liner (because the stick is a little wider than eyeliner it extends above it a smidge making for a sultry ombre look. I love these sticks. I have one in Amethyst and one in Sugar Frost and would love to get them in Cocoa and one of the grays. I have only ever used them to enhance the eyeline (and the inside corner with Sugar Frost - careful with this one it's kind of glittery) but they can be smudged into submission in the creases and corners too.
Other favorite pencils:
Smashbox Limitless Eye Liner - great pigment, not as smooth as the 24/7 or aqua eyes.
Clinique's Cream Shaper for eyes - great value, decent pigment, a little dry. I have a hunch that they might be discontinuing this soon as it's no longer sold at Sephora and they have so many new liners on deck.