1- Imrahil certainly has the elven blood in him, if Legolas recognizes him instantly like that. He differs from the others with the blood in that instead of superlongetivity or mighty mind powers, his ancestry gave him beautiful looks and a fair aura. The four Men with Elvish ancestry in some form or other in this segment, namely Faramir, Imrahil, Aragorn and Eomer all stand out from the crowd. Eomer and Aragorn are tall, mighty warriors, tallest in the room. Up in the HoH, Faramir is assuming his duties as Steward and cheering people up simply by his presence. But Imrahil? He's the Ultra Magnus of Gondor. To Quote the movie,

"I'm no leader,I'm just a soldier."

Of course, Imrahil survives the Pelennor intact and unharmed, something only Eomer and Aragorn manage. Makes you wonder if Legolas, Gimli and the Sons of Elrond had some sort of injury here or there.

Imrahil certainly displays some Elven traits earlier. He and his men sing into the city, and he brings hope to people around him, as the Elven lords of old did to the Edain. When he and Gandalf go, people shrink back into despair.

Beren and Luthien's tale is legendary ebcause they did what thousands of Elvenarmies could not and were under no oath whatsover to do it (Beren was, but he never promised to do it just for the sake of good). The tale of B and L is also unfinished- Sam thinks so, anyway.
Of course, being the first tale it gets more appraisal.

Mithrellas and Imrazor's relationship was also unclear. Did the Elf love him? Did the Numenorean force the Elf to marry him? Was the Sea-lust too much to take for her? She is a Silvan Elf,and they are the singers and songwriters- the Noldor and Numenoreans are the writers and chroniclers.So when you sing about something, the occasional detail disappears.

Legolas does recognize Imrahil as descended from an Elf in some point. One UUT is that the Faithful family that lived in Belfalas were pretty cool with the Elven-community there (mostly Eglain shipbuilders) and somewhere or another had a lovechild or child. The child's identity was kept secret and raised as a Man. Later, the legend was written to cover up the fornication? Even the Faithful can love the Eldar too much.

2:The presence of Eomer and the acceptance of Gandalf and Imrahil is more than enough. But Gondor doesn't need a cornoation ceremony, it needs a war captain. Aragorn will not crown himself until Sauron is beaten. It's strategy and time constraints. Also, he announces that Gandalf is the boss for the moment. If he were King, people would suspect that Gandalf is operating Puppet Aragorn.

Legolas isn't a Captain leading an army, he's essentially a soldier in Aragorn's group. The Sons are allowed in because they came from Elrond and represent him. Gimli himself is of the Line of Durin-you don't see a Dwarf-army coming down the road, do you?

*ignore the salesmen*

There is but one task remaining in Arda-we,the Dragons of Valinor will make it happen.

Lone resident of the Republic of Gondor

PO-TA-TOE-S not PO -TAH-TOE-S!