For the average person, I think the answer’s going to be “everyone is different.” But conveniently you ask for the ideal, and to that I have an explicit Braisa for you (quoted as Avos 6:4):
כַּךְ הִיא דַּרְכָּהּ שֶׁל תּוֹרָה, פַּת בְּמֶלַח תֹּאכַל, וּמַיִם בִּמְשׂוּרָה תִשְׁתֶּה, וְעַל הָאָרֶץ תִּישַׁן, וְחַיֵּי צַעַר תִּחְיֶה, וּבַתּוֹרָה אַתָּה עָמֵל, אִם אַתָּה עֹשֶׂה כֵן, (תהלים קכח) אַשְׁרֶיךָ וְטוֹב לָךְ. אַשְׁרֶיךָ בָּעוֹלָם הַזֶּה וְטוֹב לָךְ לָעוֹלָם הַבָּא:
This is the way of the Torah: Bread with salt will you eat, water in a small measure will you drink, on the ground will you sleep, a life of pain will you live, and in Torah will you toil. If you do this, “You are fortunate, and there is good for you” - you are fortunate in this world and there is good for you in the World to Come.