One thing I'd like to see less of in the next series is the human-centred preachiness. There are a few stories and plots in Trek where our heroes disagree with the way things are done as it offends their human sensibilities. Such a standpoint is highly judgemental and elitist as it applies a morals and beliefs of one race as better than others who have been evolving and changing for millennia.
This is part of the reason I want more aliens on the next show, to get some different perspectives on the situations the crew comes up against.
I agree. One of my favorite Ferengi "bits" ever was in DS9 when Quark proudly told Sisko the Ferengi were better than Humans because Ferengar had nothing like the Holocaust in its history. Likewise he had been shocked to learn Humans sold an addictive deadly poison to their customers (tobacco). In fact I loved how we came to genuinely understand both the Ferengi and Cardassian cultures in a positive or at least sympathetic light during that show--in no small part because of constant interaction.
Curiously, this didn't apply to Bajoran culture. Probably because of religion. They established their faith as central to Bajoran life and civilization, but even now I've no real idea what the tenets of the faith are!
I came up with an idea soon after VOY ended, and mentioned it in some groups and to fans. Almost all of them were horrified. The notion was of a race whose sun was about to emit a giant flare, scorching the planet with radiation. Said race almost had warp drive and after first contact begged Starfleet for the final secret with which to save their species. And were refused, because of the Prime Directive. Turns out there were survivors, each of whom had gained the psionic ability to turn a warp field into a transwarp one. They hired themselves out to anyone who'd cut off all business and diplomatic ties to the Federation--Klingons, Ferengi, Romulans, Cardassians, etc. They were enforcing a total boycott and isolation of the UFP, until and unless the Prime Directive was repealed. These aliens weren't evil. They had a perfectly valid POV, and pursued their goals in a peaceful manner--even perfectly willing to help out any world that seceded from the UFP.
Frankly the amount of argument made me think I had a good idea. It seems just more dramatic if our heroes have to genuinely question their own beliefs. Much more in keeping with such eps as "Devil in the Dark" and "Balance of Terror."