After days of information overflow, the decision wasn't actually that hard at the end of the day, and as soon as I said it (to the vet), I knew it was right - my beau will remain intact, at least till he is 2 years old and hopefully even longer. Unless his temper changes in any way, but I have no reason to think it might.
Female bs are definitely not messy! I was so pleasantly surprised when my deceased girl came into heat of how little she bled, but also how clean she kept herself and her surroundings. But then she had a 1st phantom pregnancy (something I knew her mum suffered from frequently), and as well as that she had a fairly huge hernia, so eventually I had her spayed and at the same time she had her hernia repaired. She was 20 months old when she was spayed, so pretty mature I'd say.
Thank you for all your responses, it certainly got my brain churning!