Honestly, I don't care at all about these things. With all of the complaints regarding gameplay right now, it does sound hypocritical of me to dislike a feature that is purely cosmetic. However, please at least listen to the reasons why I do.

Lack of Presence:

The only time you see a person's Battle Banner is typically for a few split seconds at the start of every match.

And that's it.

Now yes, I know technically you can see whatever Battle Banner a player has set on their profile, but who genuinely does that willingly? The only realistic circumstance I can see a player visiting another player's profile in general is to copy their deck, in which case they won't give a crap about what their banner looks like. Who visits player profiles JUST to look at what Battle Banner they have?

Other than that, Battle Banners aren't present at all during the match. By the end of the battle, you probably have already long forgotten what Battle Banner the opponent was using as you move on to your next battle.

Heck, not even YOU can see what it looks like during battle.

Frustrating Banner Box System:

As someone who already despises lootboxes, crates, and lucky draws, Banner Boxes really grind my gears with how stingy their drop rates are. Maybe it's not necessary for Banner Boxes to state the drop probabilities for each Banner, but it would be appreciated.

Another Currency for Horrible Shop Offers:

Ever since Battle Banners were introduced, they too have fallen victim to being present in awful special offers. Whether they are bundled with other items, or they are the offer itself, Battle Banners have an awful tendency to be ludicrously priced for the lack of effect that they provide.

I've seen Banners in the Shop priced at 200 Gems or more, just by themselves! This won't be appealing to the average free to play player, even for those who enjoy cosmetics. You can argue that Emotes in the Shop are more expensive in Gems, but I argue that at least Emotes are more useful and impactful in a player's experience.

When people repeatedly see Battle Banners present in overpriced offers, it conditions them to lump Battle Banners with "the group of crap that Clash Royale always has in the special offers", along with things like Boost Potions (and these actually have a gameplay effect lol).

Minimal Changes:

So far, there have been minimal changes to make Battle Banners more standout. Animated Battle Banners were introduced a while ago, but they have currently only been obtainable within the Diamond tier of Pass Royale, yet again favoring those who spend money on the game.

Honestly, for a feature that is meant to be purely cosmetic, restricting an animated aspect to those who pay is kind of a jerk move.

Conclusion:

To conclude, I don't despise the concept of Battle Banners in its entirety. In fact, during my free time, I have found some of their artwork to be especially beautiful or funny. However, their massive presence in horrible special offers and minimal presence in almost all other areas of the game makes it difficult for me to get excited about them.

If I were to change how Battle Banners worked, I would perhaps have the Banner design hang from the user's sides/bleachers of the arena, displaying it for viewing by both the opponent and the user. Alternatively, the Battle Banner's design could be etched into the Arena's floor on the user's side, although this might cause gameplay issues with colorblind players or those with poor vision.