Give Discovery a second chance? Nah, not now. Maybe in Season 2, if they retool... but everything that was wrong in the first half of the first season is still basically wrong in the second half, with the added frustration that it abandons all the interesting questions it started to set up in Chapter One in favor of TWEEESTS.
Give Enterprise a second chance? Yes, I think you should. Around the middle of Season 3 (so, right around where you stopped watching), Manny Coto began to take over as showrunner. The show pivots drastically. You can see hints of this as early as 3x12 "Similitude," but there's still some real clear "filler" episodes after that (CARPENTER STREET AUGH). I'd say the transition to CotoTrek is complete with 3x18 "Azati Prime." The Xindi plot gets substantially tighter from then on as the season builds to a climax. Season 4 opens with a (fairly weak) two-parter that was designed to put the Temporal Cold War arc permanently to bed, and from then on it's Manny Coto's show. For the first time since DS9 ended, Star Trek dared to try new things under new leadership, and Enterprise fully embraced its identity as a prequel that wasn't embarrassed by the rest of the franchise (which ended up giving it power to tap new stories that it couldn't tell in its early hold-continuity-at-arms-length days).
I'm not going to promise that you'll love the back half of ENT. (I did, but I am also fond of the first two seasons of ENT.) What I will promise you is that it's very different from the first half, and it sounds like it's different in ways that will ring your chimes. (Although you may still hate it, it will at least be for different reasons.) So, yeah, give Enterprise another try.
That goes for all y'all. If you never finished Enterprise, go back and give it a try now, especially if Discovery is making you frustrated.