In most cases, I wouldn't support cutting the number of the actual categories featured, since in my opinion, this is the moment for those who are usually neglected and forgotten to shine. Actors and directors are usually well recognized for their contributions by the public, but cinematographers and production designers and those who have less visible roles in filmmaking are not, and the Oscars should be their time in the spotlight!
I would support the Academy strongly encouraging presenters to avoid making political speeches. The only exception I would make is if the movie itself dealt with a social or policy issue and the speech is tailored to highlight or further advocate on that particular issue. In my opinion, the Oscars are usually an inappropriate forum for unrelated political speeches. Those who agree with the points expressed end up cheering, while those that don't end up being upset, and I honestly don't think it serves any useful purpose since very few, if any, minds are changed as a result.
I do feel the Oscars need to be much shorter. To do that, I'd support the suggestion to only feature the best song winner and not have all of the nominees give performances. I would also be open to KC's suggestion to cut that Oscar category entirely. I'd also get rid of a lot of the skits and filler that is supposed to be funny but that almost never ends up being so. For example, this year it was pretty dumb to have tourists walking around and meeting stars at the Oscars. Getting rid of the songs, the skits and other filler that is really not entertaining might get the Oscars down to 2.5 hours, which would be a much better length than the current average runtime of nearly 4 hours! I think one of the reasons the ratings are declining and that the Oscars are not watched by most people is that they are just too long.