For the record, I enjoy both TOS and TNG...but one thing that always bugged me about TNG was the way it swapped the Klingon and Romulan traits established in TOS. Romulan culture, as portrayed in the TOS episode "Balance of Terror", was as a complex, honor-driven society and it was the Klingons who were hostile, scheming, and warlike. I read an interview years ago with a TNG writer whose name I don't remember who said something along the lines of "we thought it would fun to get creative and swap the traits of the Klingons and Romulans".
The decision to make Worf a bridge officer may have made this swap desirable. If it hadn't been done, would you have preferred a Romulan senior officer with Worf's traits? Maybe so, but viewers of the old series had certainly seen more episodes with Klingons than with Romulans (indeed, Romulans are featured in only two episodes, "Balance of Terror" and "The Enterprise Incident," plus a few lines in "The Deadly Years"). The idea of a Klingon who had
to be something more than "scheming and warlike" fit well with the Federation-Empire rapprochement that made Worf's service in Starfleet possible.