I would agree in getting something mid range is better to start off with, especially if you are not sure what shaft length you like. For playboating you generally go a bit shorter than for whitewater and if you have had a shoulder problem then a smaller blade size is also a good idea. Be aware though that either of these will make the paddle a lot harder to roll with until you get used to it. If you like werner paddles (and who doesn't) there is a load of information about paddles on their website and it even has an Online paddle fit guide to narrow things down a bit.
www.wernerpaddles.com
If you have the cash to spare then I would spend a bit more on another paddle about a year down the line when you know what you want and not buy another boat just now. When people are starting out switching from boat to boat makes it harder to learn tricks (like switching from car to car learning to drive). You should also get some airbags for your boat if it doesn't have any, and a sponge to get the last drop of water out of it is 99p well spent.
Personally I paddle with a full carbon werner player cranked shaft which I think is 194 cm long, but I wouldn't call it mid priced! Werner do do a basic range called Rio which you could look at.
Oh and when you do get a nice expensive paddle don't sit on it to get into your boat, please no

!
Hope this helps,
Neil Newton Taylor
www.swiftwaterrescue.at