Latin/Greek is commonly used for Amarr, both by players and developers. Arabic/Persian/Hebrew is also used very regular, especially in nomenclature. Many Amarr NPC ships have either Arabic/Persian/Hebrew names (Tanakh, Muzakir, Tamir) or they have names of Roman popes (Sixtus, Donus, Agatho, etc). The bestower also used to have Greek letters, and there is the oft-referenced Ardishapur =
Ardashir+
Shapur connection (both Persian).
Ergo I'll use all of those as inspiration personally, though I try to focus on the Arabic/Persian/Hebrew angle because Latin is
always used for 'empire/religious' factions in games and is thus rather dull for me. Plus the Ardashir/Shapur thing makes me think of the Ardishapur area probably having more of a Persian dialect, and Sami is Ardishapurian, where other regions in the Empire might have more Latin/Greek ones. Amarr's large enough to have multiple inspirations as regional variations. Where I most often personally use inspirations from these languages is in ship names, as I try to avoid English ship names wherever possible. Typically I try to go for a name that evokes the general idea of that class using word(s) from one of the above languages (IE all of my battleships are named for apocalyptic/end times events because Amarr battleship classes all have those. My geddons are Gehenna (greek/hebrew), and my apocs are Qiyamah (arabic). I'd probably go Jahannam (arabic) for an abaddon, if I had one).
I don't mind specific references to RL usually, depending on what it is. When it's actually an IC reference to a specific RL person or place where such a reference otherwise couldn't exist (Stockholm Syndrome), then I'm iffy on it. Otherwise I don't mind too much.
What I absolutely despise is people using RL languages in actual IC dialogue. Like, full sentences. A) The translators are supposed to translate all of that anyway, and B ) I don't want to have to copy-paste everything you say into an online translator just to be able to properly RP a character who is supposed to understand that language's in-game counterpart.