I wouldn't say its "too long", there will be a ton of folks who took a year or two off. The risk with taking time off school, in my view, was that you get just comfortable enough & make just enough money that you think you don't need to go back. Then you never get licensed, etc.

I also think it depends on what kind of program you plan to attend. If you're going to leverage your undergraduate degree into getting into a 2 year program, then the extra year isn't a big deal. If you're going to already be taking "unnecessary" time going to a 3-3.5 year program after a 4 year undergrad, then you may want to consider going back sooner (assuming you can afford it).

I had the mindset that if I ever took a break from school that I wouldn't start again, so I went straight through. But my overall plan was centered on getting licensed as fast as possible with as little debt as possible, it depends on everyone's individual goals.

Why the italics?

Not too long at all. 

I took 4 years between undergrad & grad school. I worked some, traveled some, worked outside of architecture some (thanks recession). Overall I'm glad I took the time I did, since it allowed me to mature a little, and get a little industry perspective, and refine my interests and goals just enough to where I wasn't blanket applying to The Top Schools but targeting a few very specific places that aligned with my professional & non-professional interests. I'd recommend anybody take a few years gap. You'll learn a lot more than you expect.

I recommend it. It takes time for your mind to absorb what you have already learned. Imo too many people go into graduate school too soon. Enjoy the journey. You will get there soon enough.

Too long? I had a classmate that went back to grad school in his 50s so...

Not too long. I took 4 years between which was 1 year longer than I wanted but ultimately everything worked out. I would say the sweet spot is 2-4 years. You need enough time to really break a lot of the bad academic habits and get a taste of producing real work. I assure you that you will find yourself so much more prepared, focused, and with better endurance than any of your peers that went straight through. When you get to graduation, you'll be worth a lot more too. Most of my peers in graduate school that went straight through had all the same bad studio habits that they had in undergraduate, and by the time third year rolled around they were understandably burnt out. My peers who took a few years in the profession were able to blast through production work and get more sleep at night while producing relatively equivalent work. 

Beyond all of that, this is a great opportunity to figure out what you are really interested in for graduate school other than the degree and ensure that you apply to the institution that best aligns with how you see your future. 

All work experience is "good" in an ontological sense (and often more valuable than the same years/hours spent on more education), but there's a huge caveat: Not all work experience is necessarily equal on an architectural license track.

Look into your State's requirements for AXP experience - I don't know if this is still the case or not, but when I was pursuing my license there were some States (and NCARB, IIRC) that wouldn't recognize AXP(IDP) hours obtained before your degree, which in your case could mean setting yourself backwards. (I spent 1.5 years in an interior design firm that didn't count toward my license eligibility - I don't regret the experience, but I wish I'd at least been aware that it wasn't moving me toward my eventual license.)