I enjoy the game for some time now, however I left for a convention and did not play for eight days, I had a strength of 13 when I left, I was attacked every day for 8 days, NOW the strength level is 5 !!! The cost of strength did not go down with my rating, it will cost 30 Gold Tags for 1 increase. In the meantime each attack will lower the strength even more. It will take about 3 days to acquire 30 Gold Tags.

I see no way in catching up.

May I suggest that the cost of strength be equal to the current level. Otherwise there is no way to catch up, if your attacked every day by the competition, and attacking every else seems to be the only goal in the game.