I absolutely would not get bored and I speak from experience.
We have been to WDW every year except 2 when my DS was first born since 1995. We started out doing 13 day trips and have done as little as 7. We are now up to 15 or 16 day vacations and I wouldn't trade it or change it unless it was due to time constraints or other factors.
Last year we did 2 weeks in the summer. We did 2 days at the beach and 1 day at Busch Gardens Tampa. We even got to see the space shuttle take off from Titusville. This was by far our best vacation we have ever had. It was our first summer one and it really got us hooked. This year we are again going for 16 days. We plan on doing 2 beach days again and 3 days in each of the 4 major parks plus a half a day extra in MK. Will we get tired of WDW?? Absolutely not. The beauty of having more time is that you are not in a fever rush to see everything in a few days. We can take our time, stop and smell the roses, ride things more than once if we so please, eat at more great restaurants, swim more, take more time for doing the non traditional stuff (looking for hidden mickey's, taking a different path or trail, stopping in AK and really looking and enjoying the little exhibits on the paths, looking at the details, etc.). We get to spend more time in inoventions, which we can't do on the shorter trips.
Plus you have a 1 year old. I remember what it's like to be at WDW with a younge one. It takes A lot longer to see everything, from manuvering the parks with a stroller, naps, baby swaps, etc.
Have a great vacation and don't second guess the longer time. You will have a blast and it may turn out to be your most enjoyable vacation ever.