I think it is fine to talk with players and their families as soon as their season is over about opportunities for next year, or even giving someone a card when in season and saying hey, I'd love to see you try out for our team for next year. But going to other team's tryouts to poach, or just flat out offering a spot while still in season are not right in my eyes ... too difficult for some of those players to keep focused on their current teams, and too hard for parents not to start talking or bragging about, and screwing up the cohesiveness of the current team and parents.
As for coaches, I feel most of them should have the maturity to be able to be approached by someone about coming over to another organization the following year without it affecting their performance or the team chemistry in the meantime. But I do not understand many of the wholesale changes of teams from one organization to another. While in some cases, I can understand it when it can be a real step up to an organization that has a proven record of showcasing the very top talent, but in other cases, it just feels like empire building or lining of pockets.
Just my opinions ... I might could be convinced differently on some parts of this ...