Ok....
I'll take the issues in turn and offer the best advice I can. We have a 14 month old Springer btw. Love him to bits, but you have to invest time and energy into him to keep him calm and placid.
Toilet - Our dog won't go out on his own, we have to go with him. The breed trait is that they love to be with their humans. We just go out with him, but he goes to the toilet on command, so when convenient to me in the main (apart from first thing etc). I don't see going out with him as an issue to be honest, he loves to be with us, we go with him 
Weeing/fear of dogs - I really think you need to get the advice of a professional, this to me seems a sign of stress and anxiety. Make sure the professional only uses positive methods. Perhaps if you say the general area, folk may have a recommendation. You can counter condition, but it will take time and energy.
Food - don't leave it out! Teach the 'leave it' command. 'wait' is good for self control too. 'Wait' before he crosses roads, is let off lead, before eating, before chasing his ball etc, even going through doors, not for any old fashioned 'dominance' thing, just to teach self control and reinforce.
Chews - don't leave stuff out for him to chew! Teach the 'leave it' command. Provide him with lots of chew toys, antlers, etc that it's ok for him to chew. Reward him for chewing those with treats and praise. Dogs are by nature scavengers, so he's only doing what is natural to him.
Search Kikopup for teaching not to jump. I'll also find a link for you to a Facebook page with some excellent advice. We had this issue with our dog recently, took one clicker training session based on this advice, sorted
Great website.
Dogs have no concept of what is naughty or not, they are amoral, they will display a behaviour that gets them praise or reward. The trick is to capture the behaviour that you want and reward it.
What are you feeding him?
How much exercise? Our easily has 2 plus hours a day, it's hard, they are an energetic breed.
Training will wear him out. Do you clicker train? Use Kongs? Puzzle toys etc? Springer's need to use their brain as well as their body! We train lots during the day, on walks, just a few minutes here and there, while the kettle is boiling etc. Make him think!
Mine loves 'find it', I leave bits of food round the house or garden, or chuck a toy into undergrowth while walking, they love sniffing!
Cardboard boxes with treats in work well too.
Not sure the crate should really be used to contain him either tbh 