The ideal PTC of course does not has nothing in common with bux sites. But what a real PTC should have?

Only real advertisers
And zero self sponsored ads period.

Fast payments (& very low payout)
Real advertisers mean a PTC which is not ponzi scheme. Payments can be very fast because owner has already money and will not have to wait funds from investors. With low and fast payouts, users will "see" very fast money in their AP/PP account and will not have to click for 1 year in order to earn $5.

Sustainable rates
Sustainable means low <$0.004/click. More advertisers will be attracted. These rates will be effective only in case a real script is used. I'll agree that PTC will become a very slow and boring earner, but what did you expect? Millions of dollars?

Ref bonus up to 20-30%, no ref/premium pack sales
Part of sustainable rates, ref bonus is low. Ref click must not be the most important thing at a PTC site, but advertisers. And because we know that ref packs are bot packs actually, site must not offer such options. It is Paid To CLICK, not Paid To REFER/UPGRADE/INVEST

A real PTC script
The most important thing after advertisers: A script which will protect advertisers and ensure that all members will view their ads. Users who are using ESC button and IFrame blockers will not be credited. The same rule applies with users who are surfing at multiple sites at the same time. Autoclickers and exploits, finally, will have as a result a ban only. Script will also include and some advertising filters (demographic etc). If a PTC in future can have a script like this, traffic quality will be better and therefore advertisers won't have problem to pay more than $1/1000 clicks.

Some PTC sites (wordlinx, linkgrand) seem to have real advertisers and sustainable rates. Wordlinx has an advertiser - friendly script, which pauses the timer when the ad tab is not active - although there is a simple trick to bypass it. However the combination $0.001 per click and $10 payout, means that it might take up to 3 years (yes years!) to reach and receive payment even if you are a daily active clicker!! The ideal PTC does not exist. On the other hand, ideal ponzi scheme can be considered a bux, although the money amount which is involved is low. Scammers will have somehow to "gain" experience for biggest tricks...