It'd either be awful, off-brand menacing, or completely busted, because tag damage is such a powerful buff and 7 accessory slots is a lot.
That's a very good argument that I have failed to consider. I was thinking in isolation which I failed to consider that you can have up to 7 slots. Even if we did a maximum of "+1 Summon Tag Damage" Then yeah, accessories alone make more damage than most pre-hardmode whips. I mostly gave accessories a passing glance because they're not that interesting compared to weapon modifiers. They don't change the behaviour of the accessories in any way, just giving passive boosts.
I had considered that, but that's the sort of addition that only sounds good on paper. An ammo consumption reduction would just be bad, flat out. You would never want that. Ammo stacks to 9999 now and it's very easy to get, it's just adding a new quick/arcane modifier.
I've also figured that ammo isn't much of a concern to a ranger. I've only done one ranger run, but I do remember that I could have probably spend more money or effort on the materials to make better ammo. It was cool to not stress about ammo once Hardmode started (endless quiver/bullet pouch), but I could have been doing better. That's why I'm more in favour of velocity if we were to hypothetically add a new "ranger accessory modifier". But even then, it's not as exciting as Melee Speed.
The reforge system is definitely a bit flawed as is, but I also think the more ambitious the suggestion the less likely it is to happen.
I know it's not the best thing to say, but I think this would be something that the developers would have to gauge on how much they can modify. At the minimum, we are asking for number changes. If they wished to add content for this context, they could implement Summoner modifiers. If they wanted to invest more resources into this, we would see the accessories touched up on. If they for some reason decided to re-make the game, then maybe weapons could be designed with custom modifier attributes in mind (more melee weapons could meaningfully make use of Melee Speed, Minions and Sentries could be made more flexible to allow more creativity in modifiers).
I personally ask for the minimum and
some love to summoners. It would be interesting to make a meaningful decision other than Ruthless, Mythical, Unreal, and Legendary/Godly.
It would be impractical to re-write a lot of the game so that the Starlight can benefit from Melee Speed. While a touch up to accessories would be appreciated, I figure we should first cover the most flawed parts first. I do admit that I sometimes just throw ideas out there for discussion. Combined with me liking talking about game design, I do tend to digress a little bit. I should probably separate what I want and what I spitball. I want the number tweaks and a bone thrown for summoners.