I like the Ospery. I would suggest going with a bigger kite. I find a larger(7'+) kite like the Premier Widow NG is easier to fly in lighter wind than the Osprey. If you want a good light wind(3-10MPH) flier, I would suggest the Skydog UL.
I would also like to second(or third, forth,...) the advice of flying the Osprey until you have pretty much quit playing lawn darts and learned to crash softly.
As for line, I do most all my flying on 75' 100# Skybond.
Oh yes, one other thing you might do, shirillz731 is maybe give Andy at Ocean shores Kites a call. He knows just about every kite there is. He's a store owner but most on this forum will give him credit for being an all round joe. he's never steared us wrong. There's other kite stores like the kite shoppe, I don't know them, but they could be of some help.
My boys widowmaker pro sul will fly in 2 mph without moving your feet. Very little pumping and milking the wind with arm movement only. 1 mph if you step back a little as in one step every 3-4 seconds.But that's what 313$ will buy you. another is the fw zero, not a full size kite but fly's in the same wind as the wm. 0-7 mph for about 100$ or so. Its also an indoor kite as well.There's also the into the wind swift for around 100$ or so, his first low wind kite.pretty fragile stuff those kites. fly's about the same wind as the zephyr but is not much for tricks. good luck with your new zephyr, it should serve you well. A nice robust ul kite. these should be accurate wind speeds as long as my wind meter didn't lie to me:}