I think the problem with them diving, though, is how their ai is programmed. From all my times playing against bots, once their hp reaches a certain threshold, all they do is retreat, even IF all they had to do was turn around and lick you to kill you. If they tower dove all it would result in is the would die and give you an easy triple kill, without you having to actually do anything.
Also I think a problem with you having less fun with bots is because of the increase in the champion pool. Before I used to fear Annie Bots and I still do, but I never run into her anymore if I do play bots because there is a bigger pool to pull from. They should probably add more champions that have kill threat that are allow them to easily blow you up with a spell rotation.