It should have a $/s in addition to the per bar fill so that it is easy to compare the relative effectiveness of investments at a glance. (See how mediocre Lemonade stands are after the start for instance.)
WAAAY to easy, might be better with like 50 as a stat limit, or maybe only like 3 or 2 stat points a level... or harder enemies, cause i have 100 defense, 100 precision, and 50 grit, and it is not even fun, cause i can get like 180% hit chance on brute attack, and i bet the enemy has like -60% hit chance, cause they never hit me... and i have 6k hp.. on lvl 50