Do you find an any restrictions in getting award fares using companion airlines?

I'm in a similar position as the OP. I'm AA Gold this year - but I will be almost exclusively flying AS metal for the next 6 months to and from SJC - SEA. I was thinking about switching to Alaska, but I liked that AA had many more routes. I don't know where I'll be after June, so I don't want to put all my apples in one basket. My logic was: "I'll get status with a bigger airline that'll give me better options for future travel, as well as award travel options."

What do you think? Better to stick with AA or jump ships to AS?

Thanks!