I think advertising an "engaging and enjoyable" duel arena replacement that you haven't even developed yet is a poor decision that you will come to regret similar to the removal of wildy in 2007.
If there's so much rwt there then you should hire some more people in the anti rwt team instead of remove one of the more unique and played pieces of content that old school has.
Also don't ever make the same decisions that rs3 makes - that game has been a broken piece of trash for years.
Will there also be xp/hr rates available in android beta update? This is what holds me from playing osrs more on mobile, i want to see what I am gaining every hour for example. This is available in runelite and the enhances available in the next update looks a lot like some of the runelite features.