How about this recipe I just made up? Sound any good? I'm not exactly used to making my own recipes up but I looked at some pale ale recipes for reference and came up with the following. Hopefully using the kit as well will not add too much to the bitterness levels. I was planning on mashing the Maris Otter and speciality grains, then adding some liquid malt to the boiler and all the hops and sugar. Then adding the kit at the end of the boil and topping up to 50L with treated cold water. Does that sound ok? Will adding cold water give me a good cold break? Or should I boil the whole lot and then cool with my immersion chiller? What would be best for clarity of the final product? So many questions........... I know it's a bit experimental but ideally I'd like to end up with 50L of nice beer.

Malt Extract Syrup Pale 5.5 EBC 3200 grams 38.3%
Pale Malt 5 EBC 4300 grams 51.5%
Crystal Malt 130 EBC 350 grams 4.2%
Flaked Barley 0 EBC 350 grams 4.2%
Sugar, Household White 0 EBC 150 grams 1.8%
First Gold Whole 7.5 % 90 mins 50 grams 41.7%
Fuggle Whole 4.2 % 90 mins 30 grams 25%
First Gold Whole 7.5 % 5 mins 40 grams 33.3%
I'll add some Protofloc for last 15mins of boil and use the Coopers kit yeast but make a starter out of it to get the numbers up.
Final Volume: 50 Litres
Original Gravity: 1.044
Final Gravity: 1.010
Alcohol Content: 4.4% ABV
Total Liquor: 65.5 Litres
Mash Liquor: 12.5 Litres
Mash Efficiency: 80 %
Bitterness: 29 EBU
Colour: 14 EBC