It gives you plenty to practice. The radical's drills and radicals trees are an excellent idea. The only 2 negative points in my opinion are : 1 - the examples given for the usage of radicals, during the radical's drills, are not linkable. It shows you how the radical is used in more complex kanjis but you don't know what those more complex kanjis shown as example stands for (unless you have seen they before). This would be a very welcoming improvement. You could have a link for them and then have they analyzed in radical trees. 2 - In the radical trees you very often are presented with radicals denominated "not bushu" and do not receive a meaning for them, which is sad because you need to look for it elsewhere. I am not asking for exact meanings but just for general ideas for those "not bushu" kanji components since, the way it is now, they are just hovering there, without the minimal explanation besides "but bushu", which doesn't help in any way.