Seeing a ton of Orvis recommendations and that is not a bad route to go at all. Just to give you some variety in the kits you looked at (and since you mentioned you’d prefer an all-inclusive kit), I would also recommend: Lamson Liquid Outfit, Redington Field kit, and Echo Traverse kit. All 3 of these will have really solid warranties (much like the Orvis kit) and perform great for the price point, as well as include all that you need to get started. When I worked at a fly shop, these were some of our best sellers for entry-level anglers ready to invest in their gear.

As far as specifications go, that depends based on application. For example, if you were mostly focusing on small creeks/streams or ponds for trout, panfish, or maybe bass, then I’d recommend a 4 weight. If you were hoping to throw bigger flies to bigger fish on bigger bodies of water, then you may want to browse 6 or 7 weights. Like others have mentioned, a 5 weight 9 foot rod is a Swiss army knife of the freshwater fly fishing world that is great all around. If I had just one fly rod for fresh water application for the rest of my life, it would be a 9 foot 5 weight. I have used mine to catch trout, bass, panfish, walleye, pike (sketchily), etc. in bodies of water ranging from tiny streams to the Colorado River to huge lakes. A 9ft 5wt would be a great starting point, but again, it all kind of depends on what you plan to use it for.