DO NOT GET A SWITCH ROD AS YOUR FIRST SPEY SETUP. GET A MINIMUM 13FT 2 HANDER.
When you compress lines (skagit short heads 20ft) use short rods 10'6 - 11'9, trying to use heavy tips 10ft of t-14, and a half chicken fly its impossible to learn. Therefore impossible to fish properly. The way to learn on a spey rod is to buy/use a SPEY rod. With the shorter everything your timing, precision of the cast, setup and stroke all need to be spot on and refined. A longer rod, with a standard skagit head makes learning alot easier, and your fishing more efficient.
A few things you can do to help your casting:
Use tapered poly leaders, i fish a 15ft extra-fast and it gets down just fine, they have taper to them just like a tapered leader, which transfers the energy of the stroke evenly to the fly, turning it over, allowing you to fish a straight line presentation. They don't have as much grain weight to them as t-14, but i can fish them just as well as i can t-11. And they go down way faster than t-8. Quarter your casting angle depending on the water, and where you want your fly to setup and swing through. Think about where you fish, and don't just STEP CAST STEP CAST.
Light flies cast better than heavy ones. A gigantic double bunny with a pound of lead for eyes on the front to sink it, casts TERRIBLY. Where a nice marabou leech, or classic GP are sparse, sink easily with the tip and cast easily. A stiff fly to swifter currents to hold its profile, and a soft fly for the 'money' water. Plus the random snag or bad cast doesn't cost you $10 on an intruder.
Fish the water you would with gear. Just because you can cast 150ft, doesn't mean the fish are out there. Think about how many times you walk into a run with your float rod, bait up, adjust your float and flip one 10ft of the bank and....oh there's one! Undisturbed fish take the easiest route of travel, and hold tight to the bank in the soft water. Therefore fish the soft water. You don't need to cast very far with very much weight and you have a very direct feel to your fly which is usually within 50ft of you. You feel every sniff, rock, twig, white fish, etc....
I personally fish spey rods, switch rods, and single handers. All the way from dry line, to 12ft of t-17 which sinks like a half pound of pencil lead. I run flies from rabbit leeches, marabou softies, intruders and classics. I tie all my own flies. I've caught steelhead on all, and each has a different application. If any questions, just ask. Myself and many others will gladly answer.