I think you kill your own argument with the warez stuff. As far as other users go, downloading is downloading--whether the file is legal or not. And downloading files isn't what tends to bring a server to a slow crawl.
The sites that actually have stuff to move are more likely to go with a company that will look the other way, regardless of disk space or other features (Piracy was around before major overselling). They need nothing more than a static HTML page that links to the files.
Plus, if they're just looking for accounts to burn through, they'll probably look at price before space. Even with a $20 promo-code year, it's a bad deal when you lose it the first month. Better off with accounts between free & $5/month.
Other than that, the idea seems to be charge more for less. Good luck with that!
On a lighter note, I'd say your sample page is a copyright violation and linking it here will index it in search engines. Kinda funny, for someone that doesn't want to be on servers with people doing illegal activity. Keep in mind that calling it an example, and "hoping" that DH doesn't mind (not the same as getting written permission), just looks like the warez sites that say delete files in 24 hours and buy it if you like it, thinking it somehow makes it more legal. Plus, you're hotlinking their images, which is a good way to burn up someone else's bandwidth instead of your own--good thing we get so much of it, huh?
Just to address individual things you mentioned...
If that's your best guess at what the average customer thinks like, it really makes it hard to take anything else you say seriously. But...
Diskspace: Not all warez sites are full of CD rips. You don't need much space to break the law. Besides, I'd guess that programs like Limewire, Kazaa, etc... have taken some of the warez-load off of web hosts.
Bandwidth: It's probably easier to stay under the radar using multiple accounts with lower limits. If you cause a spike in BW here, you can probably count on them looking at how you're doing it. If it's legal, fine... if not, bye-bye, problem solved.
PHP & Perl: Just about everyone uses one or the other. Even a site that is mostly static will likely have at least one contact form, counter, or something that uses it. I can't picture a shared host wasting money on a stripped server that would have close to no demand.
Shell Access: I don't worry about shell access because DH knows what they're doing. Your average CPanel reseller that doesn't offer it, and claims it's for security, probably really means a) the company I resell for doesn't allow it, or b) I don't understand it, so I can't support it.
When you roll out the huge amount of servers that DH does (probably more per week than many hosts have), it's way easier to keep them the same, which surely helps keep the prices lower for their target market.
Limiting domains, DBs, etc: I don't see how that lowers abuse. I'd rather be on a server with someone that has 200 legit domains, than someone with one that causes problems. Giving a person 100 domains instead of 1 doesn't mean they'll think, "Okay, I used my 1 legit domain... time to add 99 warez sites." Same with DBs. Only takes one to bring a server to it's knees.
Then you add: "So they won't be abused, for example in order to re-sell." Uhh... that's not abuse. DH clearly states that you can resell on any plan.
"Those that cause collateral damage are file hosts/warez sites:" Naa... the ones that cause damage are the ones that bring the traffic and aren't ready for it. Downloading files isn't a big deal. Make a poorly coded site about your cat and a ton of traffic will affect other users. Those users aren't going to feel any better because you didn't affect them with an illegal site.
Or just make a single static page about a touchy subject and get the whole server attacked by people that disagree with you. You can do that with a few KB of disk space and zero server-side scripting.
Anyway, it sounds like you just want something they don't offer, which is fine... but throwing out panic buzzwords like "warez" doesn't really show a need for it.
And when you want to strip away everything you don't need, it's generally time for a dedicated server where you can set it up however you want. Then you don't have to worry about what features others want. It's also quicker than waiting around for a shared host to shift into reverse and start offering something there is no demand for.
Basically, the effect users have on each other is the result of how the host controls the situation--not the features themselves. Security happens behind the scenes at the data center--not on the sign-up page.
But that's just my opinion!
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