the invites & pin dm message & old messages disappear

hello and good morning , i got 3 suggestions i hope it will make the discord better and easier ,
1 - the invites : if the server is famous and big the invites will be limited , so i suggest to make a button to delete all the invites by one-click

2 - pin dm message : a way to pin someone message in DM it will make the commutation easier and will be a good addition

3 - old messages disappear : i have bad memory , and if i want to see an old dm i cant find it because its old and disappeared

i hope it was clear and better suggestion and im an old member in the discord i hope if those suggestions addition , and thank you <3