Re-- furler recommendation--
For what it's worth I would always advise against any furler that doesn't let you change sails on the fly-- or remove the headsail in the event of a storm or some other urgency. Many, if not all, jibs these days can be had with luff tape rather than hanks (I have one that was converted TO hanks... go figure). A furler that lets you change sails allows you to experiment with what's best to have on there. I would suggest something in the range of 135/150. Anything longer (i.e., the 170 that once was de rigueur with '70s headsail furlers) becomes a nuisance in any conditions it's not ideal for. Anything smaller makes you wonder why you put on a furler at all.
A suit of sails might include a 100/110, a 135, 150 and possibly one bigger. They can all be had with luff tape and flown in the furler.
I also strongly recommend double headsail halyards ESPECIALLY with a furler. So many people forget that once the primary furler sail is hoisted, the halyard sits for what seems like forever with the same crease over the masthead sheave and the same bends round the bottom ones and the winch, stopper and cleat. Since it never moves from this setting these areas wear like crazy and the likelihood of failure is increased. Having two halyards allows you to regularly change which one is on the furler and to replace or service one while the other is in use. Also, having a single halyard makes the very-likely catastrophe that much more of a catastrophe because you then have no remedy and must sail baldheaded in conditions that can cause halyard failure... you get the picture.
Our little Diana actually has four forward-- two headsail halyards, the spinnaker halyard, and the pole lift which is mounted high enough and strongly enough to use for flying a small jib (like on a cutter). Any of these can be used to bail us out in a catastrophe.
JC2