1) All things equal, the more quantity given to Torah studies, the greater the possible quality of Torah studies.
2) Even putting aside the debate on quality, a higher quantity of Limud Torah is in its own right a major plus. There is no minimum threshold for the amount of Torah you are obligated to know. The rule is: more is better; less is worse. And the difference between just a little more and a little less is staggering. As the Vilna Gaon points out, one word of Torah knowledge gives you more holiness than an entire lifetime’s worth of doing other Mitzvos.
And here we thought that a secular education is expensive! Its much more expensive than you think – you can acquire it only at the expense of your time and effort that you could have been putting toward becoming educated in Olam Habah.