I'd never use free hosting. But I'd consider 1GB Diskspace/ 10GB bandwidth to be sufficient / good. However.... If you're considering offering this I believe most consumers? would go for the unlimited offerings which exist.
I have used free in my life of time and I rather stay away since you can't do anything that you want to do since you not have the powers as a free person. And higher risk on what the projection is like
Free Hosting providers rely on some kind of alternative to make an income and keep their site running. However, it is very risky because if one day they realize it's not worth running, then they can shut down abruptly (with or without notice). Also, the amount of professional support you will be getting for your website's needs will be very limited, because you don't have staff who are dedicated to keep their business running. Obviously this is just a generalization, you may be able to find stable providers.
I believe https://infinityfree.net/ is one of the leading free hosting provider . They provide unlimited hosting free of costs .They don't even are looking for revenue but they are only looking for reputations .
I see that there are many free hosting services out there such as byethost, 000webhost, hostinger, awardspace, 5gbfree, etc...However, in my experience, I would like to suggest ByetHost is comparatively better than other free hosting in terms of CPU, speed, uptime, no ads and good support.
Free might be a good choice for someone that is not too serious about their website. However, free services do go out of business sometimes. If you happen to be unaware for some reason, then you could lose your website.