I want to complete a binder of the EX era and just didn’t know where to start. The only set i kind of remember is Magma vs Aqua so I’m deff unaware of a few sets.
Thanks to all who reply! 
(If you’re an uncultured swine, title is ‘‘which ex era set looks better’’) Just saved you a few minutes of google research
I really enjoy team rocket returns, the EX Cards are unique, great artwork overall and some pretty nice gold star starters
For sheer coherence of set, it’s gotta be Team Rocket Returns or Dragon Frontiers. From the commons and uncommons through the holos and ex cards, both have a beautiful organization and no card feels out of place. It is really exciting to put together binder sets of those.
Unseen Forces is a Johto-themed set executed to perfection as well. While I don’t think the coherence is on the same level as TRR or Dragon Frontiers, its still a very nice set. Some of the amalgamated sets like Emerald or Power Keepers just don’t have the same feel as the ones which had a vision from the start.
Even though I’m biased towards EX Legend Maker due to personal nostalgia, I’d recommend EX Deoxys or EX Unseen Forces. EX Deoxys has arguably the most gorgeous Gold Stars of the EX series, while providing strong holo artworks in the form of Kizuki’s Jirachi, Nakamura’s Gyarados, and Nishida’s Ludicolo, and includes prominent competitive Pokémon from the 06 era like Magcargo and Manectric ex.
EX Unseen Forces pops with nostalgia as it features the evolved forms of your Johto starters, (in holo and ex form), as well as highly collectible Espeon and Umbreon ex. It’s also a very colorful set. In fact, you have almost one of each Energy type in ex form - Meganium and Celebi for Grass, Ho-oh and Typhlosion in Fire, Feraligatr and Politoed in Water, Espeon in Psychic, Blissey and Lugia in Colorless, Tyranitar and Umbreon in Darkness, and Steelix and Scizor in Metal (sorry Lightning and Fighting!). The Reverse Holo pattern for UF is super sick too. I know some people don’t care about the Unown subset, but that’s also a cute little niche for the set. The Legendary Beast Gold Stars aren’t as expensive as the others which make them a little easier to chase. On the other hand, the exs in this set are much more pricey than some of the other sets.
TRR and Unseen Forces were the exact two I had in mind. Conceptually sound in almost every way.
I also think EX Deoxys is strong but I’m probably biased because Deoxys is one of my favorite Pokemon. Altaria, Gyarados, Jirachi, and many other cards have quality illustrations and the exs are pretty cool with the whole dark/shadowy theme. Obviously there are the Gold Stars (no elaboration needed). Only thing that’s kind of strange is the Rocket’s Raikou? That was a box topper right? Not sure about that (cool card but out of place) but otherwise a strong set.
edit @johnnymucho had the same idea at the same time as me lol even mentioned the same cards ^^ great minds think alike
I have mostly complete sets (reverse holos, exs, holos, everything) of all sets from Ruby Sapphire through TRR, and I would say my favorite of those is probably EX Dragon. I personally love how the e-Reader frame looks on the holos, and the exs from that set (namely Dragonite, Latios, Latias, & Rayquaza) are incredibly beautiful. But honestly, none of the sets look bad. Each of them has their own unique aesthetic value. Aside from Dragon, I also really love TMTA and TRR (start with the former since TRR is 100x more expensive). If you’re looking to start collecting EX-era sets, just start with Ruby Sapphire. It’s dirt cheap (by far the cheapest EX-series set) and quite a nice-looking set to have finished, though definitely not the nicest-looking one, IMO.
EDIT: oh, and another set that has an very unique aesthetic is Delta Species. The most similar set to it is Holon Phantoms, but I find Delta Species nicer-looking. I’m about half-way done with it and I personally think the holo rares are the best from the entire era. You have eeveelutions, Dragonite, Gardevoir, and all with Delta Species coloration.
You could look at the artists as opposed to sets. Two very influential ex era artists are Ryo Ueda and Hikaru Koike. Also theres some good Arita arts to find as well 
I really like the crystal theme of ex crystal guardians, that set has some beautiful cards in it and probably my favoruite common and uncommon cards of any set. ex Dragon is another set I really like, just amazing artworks especially the holo rares. Every holo rare in EX dragon is a 10/10
Thanks so much to everyone who replied it’s really helpful!
A little late to the party but I also put TRR and Unseen Forces at the top of the heap.
Delta Species. Blew my mind when I found out they made up an entire new region for a TCG set
All of them! Ex sets are simply the best when it comes to artwork. Ex Emerald is my personal favorite but I know I have a bit of an unpopular opinion about that one
I completely forgot about that until checking it again! That’s honestly crazy, I’d love for them to revisit delta species sometime in S/S hopefully. The idea of atypical typings is just super fun and gives the cards a chance to be something different.
As for which ex era set looks the best, it’s kinda tough. All of them have something to offer but I think the one that is the best to me is Dragon Frontiers. It’s the most well-rounded set to me, since there are sets where I like the holos/non-holos but not the ex or I like the ex but not the holos/non-holos etc. I think DF is super well rounded in that regard with Unseen Forces up there. TRR has, by far, my favourite ex cards though (rocket’s snorlax ex is my favourite ex of them all I think).
Golden sky silvery ocean / unseen forces!
I’d say ex Delta Species. Delta Species have one of the best lore in the Pokemon TCG and that’s the set they premiered in. The holos also have a holofoil that is different from any other set. They are incredibly bright and shiny and the effect covers the whole artwork and border. Holos from Holon Phantoms, Crystal Guardians and Dragon Frontiers also have the gold border, but the material the holofoil is made of changed, so they aren’t nearly as shiny.
EX Deoxys or Delta species, as they have some of the best Gold Stars and nice regular cards as well.
Every EX era set for the EXs. These cards are awesome.
Top “entire sets” for me, and I highly recommend the “stamped” reverse holo versions:
TRR for the most unique art style of all of the EX-era sets, this would be my top-rated set of the era
Delta Species and Dragon Frontiers the whole sets are great, particularly the holo rares, these are close second to TRR for me
my least favorite sets of the era are some of the early ones prior to TRR.
In terms of gold stars, I’m a fan of all but Deoxys takes the cake. Next Dragon Frontiers (Charizard), then delta species, TRR on down the line with power keepers being the least inspiring and most common (higher print run, higher pull rate)
I personally like EX Team Rocket Returns, EX Emerald, and EX Legend Maker about equal.
Although I like all of them tbh.
Greetz,
Quuador
ex Dragon Frontiers!! But I understand some people don’t like the idea of alternate typing, if you prefer normal typing my choice would be ex Deoxys
+1 for ex Dragon Frontiers, so many unique arts.