Summon size have you down? why not have it your way?

[Hoshikogi]

Well just like before, noone can really agree on their vision for the summoner.

But I had a question, is this supposed to be visible to everyone, or just the summoner?

Just visible to the summoner seems okay, but I don't want to have to yell at (or be yelled at) if someone doesn't like my huge summon or something.

I assume you are referring to option 3: ability to hide all summons on screen. If a summoner is in you're party with their Egi out, each person within and outside the party would have the choice on how the Egi summon appears (or doesn't appear) on their own individual screen. The summoner may choose to display their summon on their screen at full scale (the same way that a BLM or WHM would probably choose to "Show All" for magic spells); whereas, you and other party members could choose to hide the summon so that it does not appear at all on your screen.

For better illustration, ill provide an example:
Three players form a party for a difficult fate Boss: 1) Summoner, 2) White Mage, and 3) Bard.

1. The summoner decides to choose option "Full Scale" for their Egi (Their reasoning: to better view the placement of their summon as well as the desire for the aesthetic appeal of the largest setting for their Summoned Egi)

2. The White Mage chooses the option "Compact" for all Egi (Their reasoning: to reduce the space in which the summon occupies their view of surrounding monster, but still present in order to click the summon for healing if needed (Titan-Egi is tanking)

3. The Bard chooses the option "Hidden" for all Egi (Their reasoning: there's various key monsters (i.e. Healers/strong AoE) that need to be dispatched quickly and the use of direct targeting is most desirable over cycle targeting. Hiding the Egi makes this task easier.)