Anna, do you have Vicks Vaporub in Latvia? That’s good to have around in the spring when the mares go into season…
We have two stallions at our farm, and they do quite well with the other horses - one is an Andalusian, and the other is a Friesian. They require careful handling, but other than that, they are fairly easy to be around. They are both show horses as well as breeding stallions, and we work VERY hard on their manners. They cannot call to the mares (or geldings) while they are working undersaddle or on the lead line, and they must pay attention to the handler at all times when out of the stall or pasture. That’s a good habit to get into. Their stalls are right next to each other, and they are pastured next to each other.
It sounds like you have a good setup for a single stallion, but still be careful to never let your guard down. I worked for a stud a long time ago and I’ve seen a stallion do some damage to another horse, and would rather not see that - they are not fire-breathing dragons, but can become aggressive when their hormones get the best of their brains!