Hello Mighty Swashbuckler! Point 1 and point 2 might actually be related. I believe swashbucklers get an eagle centurion named Samocles from a quest line that's given by the guy in front of the Nova Aquila tavern. I believe his name is Pixeles or something along those lines. As to why you cannot receive that quest yet I'm not sure. Sometimes you need to meet specific requirements for quests to show up, such as completing another side quest first or passing a certain point in the main quest line. More likely that latter than the former in this case. Since you're level 64 I'm going to guess you haven't finished the main quest line? If you have, you must have worked almost exclusively on the main quests because in my experience, with a few side quests you should reach the level cap just before the end of the main line. If you haven't finished the main line yet, I would suggest you work on it a bit more and see if it shows up. If you have finished the main line and reached the level cap and it still doesn't show up, it may be some sort of bug, I would ask around or simply report it. Hope this helps!
Once I reached level 65 I got three new side quests from Nova Aquila including the guy outside the tavern. I am a privateer and I just got Argos at level 65. I got him right after I got Hawkules. Hawk guarded the door and Argos need my help to get the chain. Once that was done he joined me also. And yes, I still have Zeena to look forward. You just need a weensy bit more patience.