While I STRONGLY DISLIKE the Astros, here is what I would say about their team if you're looking for a reason to follow them:
Both teams have star players, and would be the reason I would follow either. I'm not going to go into the breakdown of each player for the Astros, but pretty much all of their good players are below I would say 27, and pretty damn talented. In the case of Carlos Correa, ultra-talented. There is no player in the MLB quite like Jose Altuve. He's so short but so good at hitting for contact and is somehow the Astros' "veteran" and he's only 26. If you're watching them, you're rooting for a team full of youth and talent, which can be very exciting. They've also added in some pretty good veteran players (McCann, Beltran and Reddick). I don't know their pitching staff or bullpen as well, but I would venture to say that youth and potential/talent is the story of the Astros team. If things pull together for them, they could be a force.
With the Rangers for example, Adrian Beltre is a defensive wizard, and pretty much universally loved around baseball for his personality, and he just so happens to be a hall of famer at third. He's worth going to a game just to watch by himself. Rougned Odor is a small power hitting second baseman who plays with a lot of passion and aggressiveness at the plate and on the field. Nomar Mazara is incredibly young and ahead of schedule with his MLB development. Yu Darvish is finally fully healthy, and can be a pitching artist if he's on his game. Cole Hamels is capable of shutting down any team any time he gets the ball. They also have some hard throwing bullpen members. Overall the Rangers have I would say more veteran players than the Astros do.
Personally I think both teams are going to be good this season, and I think the Astros could take a fairly large step up with what they've added.