Some years ago after I watched TNG for the first time in its entirety (in the 90s I only caught random episodes here and there), I started watching Voyager but I quickly gave up on it after a few episodes. It just seemed so much worse (no character caught my attention too) after watching TNG, Babylon 5 and DS9 pretty much back to back. Does it get significantly better later and does it have a proper end or was it cancelled?
All ST series have their bad, their average and their good episodes, with a smattering of Godawful and brilliant ones tossed in. I've found all of the series to be about the same with the bulk of them, with the only real difference being the number of brilliant ones. TNG and DS9 certainly had the most really exceptional episodes, but for the most part we're looking at a very slight difference in quality between the series once they all average out. VOY is just like the others in that you'll see good, bad and ugly with a couple of great ones here and there. It's possible you just stumbled across some bad/average ones. That's why you really have to stick with these things if you haven't seen them through before.
As for conclusions, DS9 did it right but that was the simple part since they'd been working the same story for 4 years. It was easy for them to spend the first hour ending the war and the second hour wrapping everything else up. All Good Things was a great episode, but it really just seemed like a great episode to me more than a conclusion to the thing. The day after Picard got his marbles back they were going to be rescuing refugees, studying some stellar phenomenon and killing time in the holodeck paripicpaing in far more entertaining realities than their own, just like every day for the last 7 years.
I understand why VOY ended the way it did, and providing closure to everything would have taken another 45 minutes or so which it didn't have. This wasn't DS9 where the final battle had been fought the week before. The only way to really do that would have been for Q to show up and say, "well, here you go, Merry Christmas" and blink them home so they could spend time wrapping it all up. Add to that I doubt it would have been as rewarding as people wanted. I'm fine with letting my imagination provide the closure, because there's a lot of stuff that they never would have hit upon. If you think about it the 4 weeks of debriefing Janeway would have been fantastic, and not something they could have done.
Besides, the best part of the post-return conclusion would have been when the temporal investigations guys showed up and said "hey, that was great try, way to go, but, uh, no!" and sent them right back to where they were, tossing future Janeway into some sort of prison.