I like to add a Guild System where every guild members will get guild experience points by battle within the guild or against another guild for every level up of the guild you will gain something

Guild lvl 5 = Gains Battle points 5% only in a guild match
Guild lvl 10 = Gains Battle points 5% and increase drop rate in a guild match
Guild lvl 15 = etc etc
of course it's better will increase the difficulties of gaining guild exp (if that's what you like)

another feature will probably Guild Ranking of course showing the top guilds (Top ranking guild will increase of the amounts of wins for competitiveness)

Another feature is Customize Guild members nickname, having dota 2 emoticons in the chatroom, Guild forum, etc

this is just some ideas that just pop up lol
Don't bash me ;w;