I like a lot of the smaller rules. Policing the luxury tax to require small teams to spend more money is a good one, for example. They also permanently locked out big market teams from ever receiving money from the luxury tax (ironically, the Phillies were one of the reasons we got the system in the first place because they argued they were not a major market team). They're expanding replay. I'm also OK with ending all those compensatory draft picks (although I do think they should give compensatory picks for rental players because they're good for small market teams). HGH blood testing is a good one as well. Expanded rosters for double-headers is very good. There's talk of split-team double-headers which strikes me as pushing it, though. More double-headers would be good, imo, both because it's a very traditional baseball thing and because it might help shorten the season.
The two big things, of course, can be cause for concern.
The expansion of the playoffs reduces the chance of competitiveness. However, I think that is mitigated somewhat. Even last season, which looked like the entire playoff system was locked in, teams made a surge to try and get into the playoffs. There's still an incentive to win the division and, if anything, I'd argue that a one game elimination makes the division more valuable.
And, yes, I see that a one game elimination is not very baseball oriented. However, baseball has always had that if there are tied records at the end. The way I view it, it's just expanding it to include the two closest teams that did not win the division.
It's non-traditional and certainly has disadvantages, but I'd say it's a mixed blessing overall.
The year-round interleague and even leagues scares me. Quite honestly, it scares me a lot. I'm terrified this might be the end of National League Rules. I don't care if the NL is the only league that still holds on to it, it's purer baseball. I think it's more exciting baseball because I value more than homeruns. However, given pitcher contracts, I think it's only a matter of time before year-round pressure of rule differences leads to a change.