Well, Intel kinda paved the way for most of the performance improvement ideas in these CPUs already. The fruit is hanging further and further up the tree.

It's unlikely that the A series would be able to compete with the Intel CPUs at significantly higher TDPs from the get go - especially when you start considering interconnections between cores etc. They might be able to get close to lower TDP desktop i5s, but then just look at the difficulty Ryzen is having at doing just that...