I can see why you want players to be nominated by us as it should be players were are targeting to win in the auctions. Maybe keep this in and ask us to send a full XI of players to you rather than a handful of names? That way you may get more names across the board?
Transfer kitty seemed fine to be at the start of the season. Perhaps then give everyone half the kitty at the halfway point plus any cash they had left from the start of the season?
Scrap double captain - Keep it balanced throughout, makes it simpler and easier for you
Other sites - Can see why you want to use dream team to get points for European games. Not sure what other sites can be used for this.
WhatsApp - I declined on this, pointed out that it's a website competition to get more interest ON the site, not OFF it.