Building up Booble infrastructure is a good way to earn good money daily.
At the beginning you will start with a small server without live streaming rooms. Here you can upload photos and your amateur films. The amount of uploads is limited, but if you continue upgrading booble you don't have to worry about that fact.
After fullfilling the last part of the tutorial (getting pro licence, search the forum for a howto) and with increasing level you can visit semester courses which will increase your filming skills (better bonuses, more actresses, better (paid) kind of films). It will also give you the opportunity to buy better Booble servers. Although they are not cheap, you should do this, because Booble money is safe (which means nobody can rob your booble server, not yet).
For collecting money from Booble you should click at the money symbol above the Booble building (at least once a day, because it will never be more than the max profit shown). When you collect money, you will also collect client growth. Keep in mind the shown values at the booble server screen refer to 24h. So after 6 hours you will only collect one fourth.
And now to the ratio of subscription price and client growth/profit. At the beginning you should get some money, but should emphasize on client growth (1-2$). The growth at low level servers comes from uploads (photos, your selfmade amateur films and the films from cruising with your car) . You can replace (the upload growth) or increase your client growth with adding live stream rooms at better servers (here you have to 'man' them and you can upgrade them too). When you reach the maximum amount of clients (of the server), you can increase the subscription price (maybe here should have a plus of 1-2k client growth) for maximizing profit. Additionally you can temporally increase client growth with spending money at advertising.
When you have the best server with all live stream rooms fully upgraded and manned with decent girls, you can earn around 5M daily. With fully build up divine actresses and continuous upload of films you can make up to 6M.