I think The Hornets will miss you
I have taken a good look and the pictures are fine. The kit you have will stop the action and get you close, particularly in good light. My first reaction would be to crop good shots tighter, watch the horizontal level, I often have to rotate shots a little to stop players looking like they are on steep slopes
I don't know if you have tried any of these sites but here are some links which I use a lot:- http://photography-on-the.net/- just about everything is covered including some superb advice from one of my favourite photographers - Gavin Ellis, you will need to dig in to find specific topics. Gavin Ellis TGS photos site for inspiration http://www.tgsphoto.co.uk/
The Non League photographers forum at http://www.nonleaguephotographers.co.uk/ where a bunch of us at all different levels swap hints and pinch ideas.
I started seriously about 5 seasons ago (check some of my early efforts) and originally learned by trial and error. I have tended to concentrate on cropping close to the action and will often upload pictures 'not of the best quality' where I feel the players would be interested in specific incidents.
Other photographers David 'Nomad' Bauckham in particular will often go for atmosphere or environmental shots. You might like to take a look at the work of Hans vd Meer at http://www.hansvandermeer.nl/ I love football and photography and enjoy putting it together but it is addictive and searching for the best shots can seriously hurt your wallet. I have just invested in the Sigma 300mm 2.8 on my Canon 50D. I am now considering the Canon EOS 7D. My kit weighs a fair bit but gets me great reach and I am trying to learn 2 camera techniques using 2nd camera for the nearer shots. Great that you are covering WSFL, I have recently had an enquiry from East Dean, maybe you could give them a visit. Rather than carry on here I will PM you before too long.
Forgive me if it seems I am telling how to suck eggs, I just hope some of this helps,feel free to get in touch
Cheers
Also a bald bloke from Horsham