What would you guys do? I am having a happy dilemma.
This year, I am coming up a special occasion — Our 10 year anniversary. I can get the 10 motif (hammered gold, TE or onyx) which was the only thing left in my Alhambra wishlist (for now lol). Or, I could get a tennis bracelet or an eternity band with larger diamonds for my right ring finger.
1. 10 motif: only piece I have left in Alhambra wishlist and this would be my first and only 10 motif. I think I’d want the TE 10 motif the most, but the onyx 10 motif wowed me so I am torn… and hammered gold (if I can pre-order) would be so low maintenance. Would not wear everyday, but if I don’t get it this year I will get it in the future.
2. Tennis bracelet or eternity band: I would pretty much wear it everyday
I plan on eventually adding whichever pieces I don’t get this time around. My lifestyle is pretty casual. And with a toddler and a newborn on the way, I’d definitely wear the 10 motif the least, but again I plan on getting it one day if not this time around.
Hi! First, happy 10 year anniversary! How special... the big 10!
My input on your dilemma...
First, I need to preface this with my thoughts on tennis bracelets and eternity bands.
I am not a fan of these pieces (tennis bracelet, eternity band) for the same reason as
@etoupebirkin. I feel they are ubiquitous, and everyone one has them, real or fake. I've gone through three tennis bracelets, upgrading each time, and after the initial glow of a wearing a new piece, I felt it was nothing special. Why did I keep buying them? Because at the time, I felt everyone had to own a tennis bracelet as a "classic diamond" piece. I did this with my diamond earrings too. I upgrade three times, and I don't even wear them at all now.
Don't get me wrong, I love a sparkly, perfectly cut diamond. I wear a boring, classic, ubiquitous Tiffany diamond solitaire as my engagement ring.

Design-wise, it's my most boring piece, but I really love love love it as the diamond is the star, not the setting.
That said, for you...
I assume you really love love love the tennis bracelet or eternity band design to want one, and it is not because you feel you should own this piece as part of your jewelry collection.
Assuming yes, that you really love love love these designs, I vote to get a giant eternity band with perhaps diamonds in a fancy cut such as emerald or asscher.
First.. the why nots...
Why not the 10 motif?
Because as you said, you will not wear it often. Get it later, not for the big 10. The 10 motif is just another Alhambra piece. Plus, I think the 10 motif is hard to wear. It clashes with a lot of round necklines, and the length sometimes lands at an awkward spot on the person. Just be sure you like wearing short, choker-style necklaces before you get one. I would wait until your lifestyle suits wearing a 10 motif regularly.
Why not the tennis bracelet?
Because, in my humble opinion, this piece doesn't make a statement. It's like wearing a gold chain bracelet, nothing special. I also feel that unless the tennis bracelet is of a significant total carat weight, you are going to feel like you have to stack it with another bracelet. This is because by itself, a tennis bracelet doesn't have presence, which is why people feel the need to stack. Which then, defeats the purpose of getting a "diamond bracelet" if it has no presence, and you have to mix it with other bracelets. The "gorgeous diamond bracelet" look is lost, and it's just now a "bracelet stack" look with the tennis bracelet being a supporting actor. I hope that made sense.
Why a giant eternity ring?
Because it celebrates and honors 10 years together! And because you said you would wear it everyday. It's not often life has these wonderful celebrations, so I would get something memorable that you love. You will have an ear-to-ear grin when you see it on your finger, as will your husband. He will feel so proud seeing you wear it. I also love love love the meaning of an eternity band...marriage for an eternity, full circle, endless, no beginning, no end.
I would suggest getting a large band as you mentioned. A large eternity band will pop! I would also suggest getting diamonds in a different cut other than round (which everyone has). I love emerald cut diamond eternity bands. I also love asscher cut diamonds, but well cut asschers are hard to find (be sure to look for those perfect windmills).
That's my vote! Just my two cents to share my thoughts. Hope it helps in your decision.
Congratulations again on your 10th anniversary!