Right on mikew!!!
Negro Leagues: OK, it was nice, when it was historically legitimate, which means the origninal pre-expansion footprint of MLB, O N C E . San Francisco never had a Negro League team, and Phoenix was a town of 15K people when those leagues died out 60 years ago. I saw a game to other day where Tampa Bay was wearing the uniforms of a Jacksonville (150 miles away) Negro minor league team that existed for a few years in the 1930s. That is not historically accurate. If the teams in the northeast and upper midwest want to honor these teams permanently, then put up pennants for their past championships and retire some of their numbers from the team in your town.
Spanish: Pandering. Did MLB teams in the 1920s pick days to wear uniforms in Yiddish, Italian, Polish or German? No, they were a part of a wise social system that knew that a common language, no matter a person's ethnic heritage, was important and which encouraged newcomers to, without losing their culture if they so desired, learn the common language of the country in which they proposed themselves to live.
Military: Wearing a cammo or R,W,&B decal does not "support the military". It is, again, just pandering and feel-goodism. If you want to "support the military", join the USO. Get involved in politics and support whatever policies you feel are most condusive to their future success. Say thank you to a man or woman in uniform. Spend some time at a VA Hospital.
General Old Uniforms: As noted, the best uniforms are the ones that have not changed much. Yankees. Cubs. Dodgers. The original teams need to pick a style from the past and STICK TO IT, and the expansion teams need to pick uniforms that pick up on that style. I saw Tampa Bay, which apparently never wears its own unis, in 1967 AA Tampa Tarpons unifoms, which were just the 1960s era Reds uniforms with a modified logo (Tampa was a Cincinnati farm team). Ugh. Cleveland has like 20 uniforms, because, Cleveland never was any good and changed uniforms every few years to get a never-ending series of "fresh starts" and now it wears all of them this year.
And, while I am at it:
Batting practice uniforms have to go. WHITE shirts at home, grey on the road. No colors.
And, special memo to the Blue Jays and the Mets. Black is NOT one of your team colors. The Mets, with their systhysis of the Giants and Dodgers uniforms, have one of the best expansion uniforms. They toss that away to were sloppy black batting practice uniforms. Toronto likewise had the last natural team name left and picked up so very well on the traditional Toronto color of blue and had a cap logo that was just awsome. So they trade that for a black whatever with a pi**ed off looking bird inside a "J" (not even a "T").
Blue skies. Green grass. White uniforms.