I would highly recommend Wycombe Air Centre - they have 2 FIC instructors and so can offer part time or full time courses and have a great reputation
As for finding work afterwards - I wouldn't be too despondent... the so called large amount of FIs looking for work are likely to get swallowed up fairly fast as summer approaches and I know that all the last year of WAC instructor course graduates are all working in instruction as they had wanted and I don't see how this should change. Some issues can occur when schools want to employ people who have done the course with them over non-home-built instructors and this seems fairly reasonable.
All I can suggest is going to see all the schools within a reasonable distance from you and have a chat. Do your course where you get the best vibe!