Bajorans are definitely boring
and inherently obnoxious, not to mention, eyesores due to their hideous noses, earrings, and clothing.
DS9 would have been much better if they were not part of the concept at all.
When they ditched Bajoran stories for the most part to focus on the Dominion instead (end of Season 2 and on) that is when DS9 became a great show on the whole: because Bajorans were dragging the show down and wrecking its potential prior to then.
There's a term for this (literally); it's called dramatic conflict and it is what makes for good fiction when executed properly. I'm not sure how, exactly, that is anything but antithetical to the word 'boring.'
I am a huge advocate for dramatic conflict. In fact, since only TOS and DS9 have it, that is one of the main reasons I find the other Trek shows to be unwatchable.
However, the Bajoran/Cardassian conflict was executed very poorly.
~90% of the 'conflict' screen-time was devoted to having Bajorans whine incessantly about how they were oppressed during the occupation, to anyone and everyone under the sun (most often, non-Cardassians), and even the same people hearing it (Sisko etc.) and the very same people whining about the very same things (Kira etc.) umpteen times. That is not entertaining, that is simply unbearably annoying. That is why the Bajoran race fails at providing interesting dramatic conflict.
Please enlighten me - what makes good dramatic conflict? Two groups of people who have no problems in their past whatsoever? Two groups of people with very few problems that they will solve until the end of the episode? What exactly?
Good dramatic conflict: both parties have an interesting point of view and neither can be said definitely to be entirely right or wrong. I.e. The Sisko vs. Weyoun scene in Call to Arms where Sisko refuses to let more Dominion ships through the wormhole - an excellent example of perfect dramatic conflict. It even includes nuances like brinksmanship, with each party lying to each other in a polite way.
Another great example of dramatic conflict: Hippocratic Oath. Both O'Brien and Bashir have a valid point of view regarding their dispute, therefore the conflict is fascinating to observe.
What is
not good dramatic conflict is a hideous-nosed person whining: "O, woe is me! Cardassians have oppressed me! Pity me! Listen to my whines about how many times and in what ways we have been oppressed! (even though you have already heard them all before, several dozen times in the past, from other perpetual whiners of my race)"