Originally Posted by maritimesailor

One line system:
-Physically easier to hoist (2:1 advantage on the halyard)[...]
-Takes slightly longer to hoise (twice as much line to pull), for me, about 2-4 seconds longer (yes, I'm not the fastest hoister, I'm also not the slowest wink )

Two line system [...]
- Faster hoist (direct 1:1, I can get it up theoretically twice as fast)
- Harder hoist (1:1, taking the direct load of the kite).[...]

You can also have a 1:1 single line system, this negates some of the disadvantages you list in the one line system. It's my weapon of choice with the caveat that I don't have the same requirements as I sail mostly solo.

A disavantadge of the separate tack line you don't mention is the starboard rounding issue. Doing starboard rounding of marks with the tack line nicely routed to the wrong side is a challenge. Not an issue at the top level, where starboard rounding is rare unless you're doing match racing, but for club racing or long distance it's not that uncommon.