I'm in the market for a light/medium weight shell that is breathable and at least average in the wind and rain resistance.  Money is not a concern so Arcteryx type suggestions are welcomed.

I'm not decided if I want hooded or not.  It's mostly for everyday use, perhaps training in light rain, summer trip to Ireland/UK this summer.

I already have a superlight summer rain shell and plenty of heavier fleeces but hoping to carry just one thing for this summer's trip and if it packs small when not needed, even better.

A LOT of the UK backpackers wear Páramo waterproof jackets, they use a directional water transport fabric instead of a WPB and it’s supposed to push out 80% of the moisture from your body while not letting any in. They ain’t cheap, and I don’t know if they have any US retailers.

thanks, will check it out

Kuhl makes some interesting options.
Outdoor Research as well.

I'd make a purchase decision 100% based upon warranty. I buy good gear, scan the receipts and store them online and will warranty something in a heartbeat if it isn't holding up.

These waterproof shell jackets are notorious for failing. At the time I bought my first one an epoch ago North Face was a pretty reputable company and stood behind their gear. Now I don't think their warranty is what it used to be. I recently replaced the replacement shell jacket they sent me and after shopping around I went with Patagonia. It's nothing special - a basic shell, it was mid-range to higher end price wise although I bought it on sale. It has one of those flat waterproof zippers which are nice. I heard Patagonia really stands behind their gear. Hopefully I won't need to find out.

What do you consider "light-ish"?  16oz, 12oz, 6?

I'm of the opinion that WPB shells wear out from the inside first.  In this vein, I will recommend a slightly heavier 3-Layer WPB shell, as opposed to the lighter, less expensive 2 and 2.5-Layer shells - in my experience, the WPB membrane just degrades too quickly 2 and 2.5L garments.  I will, however, go with 2.5L shell pants for two reasons: first is the regrettably consumable nature of pants owing to abrasion and such; and second, legs just seem to dry out more quickly than my upper body when I'm on the move.

I have an older model of the LL Bean Pathfinder jacket - with a very supple outer fabric, and I really like it as a casual or backpacking shell - fairly compact, comfortable, weight on par with my Arc Alpha shells but with a much more easy going fabric, and the very important aspect of having low-position hand pockets.  Pockets on Arc Beta and Atoms insulating layers are cut high to allow unobstructed access while wearing a pack belt or harness, and as such, they are pretty miserable pocket for general loafing around.  The LL Bean pockets are smartly located for the best general use.

The new Pathfinder is Gore-Tex, 3-Layer, instead of the 3-L Tek2O that Bean used for my jacket, and with that, I think the outer shell fabric isn't going to be as supple as what is on the older version - the photos make the fabric look a bit more technical, a bit more glossy, a bit more crinkly - but that type of face fabric probably holds a DWR finish better than what Bean was previously using.

Spent a week hiking Scotland this past fall. Merino long sleeve base layer, a midweight fleece, and Patagonia Granite Crest rain/wind shell. The fleece didn't see much use while I was moving, the Granite Crest was superb in the rain.