get a thatcham approved alarm. it can bring your insurance down a little. tell them you remove a wheel at night. and then ask them of approved ways to lower the premiums, they should have a list of things that as a company they want you to do.
but ultimately the only way to lower your insurance is to build your no claims, drive safe and avoid accidents, never accept the first quote, ring everyone and their dog for quotes and get them to justify their price. at least that way if your premium stays the same you will know why.
different jobs also give different prices, i am not saying you should lie to your insurance company. however, an it worker can state they are a data analyst which lowers premiums. maybe only by a few quid. but it is a few quid in your pocket not theirs.
hope some of this helps.