I live in Southern California, so take what I say with a grain of salt.
I hate to show up the new guy and oppose what others have posted, but I think a kit is a terrible choice. It appears to me that most kits are put together by marketers or bean counters, not fly fishermen. There may be exceptions out there. I have not checked them in several years.
You are in Washington, where most fly fishing is done with a 9-weight rod. With salmon and steelhead in the mix, you need the extra power to land the fish. I've never seen a beginner kit with a 9-weight rod, they are mostly 4- and 5-weights. If you are planning on fishing only tiny creeks, you could go as large as 6-weight, but I would not.
The reason is due to the recent profusion of lines, and the advantages they offer. I can now present a tiny fly in still water as delicately with a 9-weight as I can with a 4-weight, and I can do a WHOLE LOT MORE with that 9-weight rod. Like fishing for steelhead, salmon, largemouth and smallmouth bass, pike, muskellunge, tuna, striped bass, bonefish, and, yes golden trout in the high Sierra lakes, even in the wind.
Rio started making many line designs for specific situations, and many with interchangeable tips. Sink tips with 2-1/2, 5, 10, and 15 feet of sinking line. Sink rates from 1 inch per second to upwards of 9 inches per second.Super short, heavy tapers, super long tapers, special tapers with matching bellies for every species in the temperature range you'll find them in. Lead core substitutes called T-8, T-11, T-14, T-18 that are more flexible than leadcore and offer different sink rates.
Other manufacturers have joined in the fun, so now there is a HUGE choice of lines.
I can use a 7-weight short Skagit line on my 9-foot, 9-weight rod with a 4-weight long-taper looped on out in front of it (the weights of the two added together works for a 9-weight, about 425 grains) to throw size 20 black gnats to brookies and golden trout in winds that would have prevented me from fly casting with a 4-weight rod, and present delicately as a 4-weight in no wind.
As this concept spreads, the smaller rods may become obsolete. I no longer have nor need rods under the 7/8/9 range, although I did keep a 7/8 slow action rod to convert into a light Spey by adding 54 inches to the butt (I used a graphite golf club that bent about right) and making a new handle, reel seat, and ferrule. I can see keeping a 3-weight if I had and wanted to fish for 8-inch trout in a tiny, local creek, but my fishing time is too important to me for that.
I've been setting beginning customers up with 9- to 12-weight rods for a decade now. They love to tell me about catching 4-1/2 pound corvina in the surf, largemouths over 9 pounds, striped bass, bonito, calico bass, yellowtail, rooster fish, and also trout in the local streams.
We're using 12/13-weight sized reels just in case the extra backing is needed with really big fish. A few have been glad they did get a larger reel - one caught a 24 pound yellowtail, another has wrestled several striped bass from 12 to 31 pounds and a 28 pound king salmon. My best on the fly rod so far was a 12 lbs ling cod in the surf. YES, a ling cod in about 2 feet of water. The big reel will nicely balance your Spey rod, should you elect to go that route in the future. Most guys are getting at least one extra spool for a second line, usually one floating and one sink tip. I carry a 3rd if I'm going to a deep, fast river spooled with Rio's T-14 and lots of backing for weighted flies and deep work.
Advanced fly fishermen have gotten in to Spey rods, casting, and methods, still others are finding Switch rods are about right for their waters. Don't worry about Spey nor Switch rods yet. Just learn basic fly casting first. A lot of us fished 40+ years without needing to move up to Switch or Spey rods. They are for BIG water, though you have plenty of that in your state, so you may end up with either or both. Those are more expensive rods/reels/lines, and will prove a headache until you are ready for, and need such a rig.
Take lessons from an FFF certified instructor when you are ready to improve. Go on a trip with a local fly fishing guide. Your learning curve will be much happier.
Good luck!
Sharpen your hook. Check it with a 20X magnifier. Always use a new tippet.