I fully agree with this. I've been playing for about two weeks now, very much enjoyed many aspects of the game, but now the battles and everything else start becoming a bit pointless because of the lack of strategic purpose.
I have more gold and more coins than I will ever need, my castle is fully upgraded, and there's no threat or goal to strive for any more. This is especially true because levelling up troops is only a small tactical advantage. It gives you a few more tactical options, but you will simply face stronger opponents.
PvP is still a fun side game, but a strategic purpose would give the game a longevity that right now is lacking.