You can NEVER have too many credit cards.

FICO score high achievers have 6 credit cards on average and i have 18 personal credit cards with over an 800 FICO score.

It's clear that having more card does NOT hurt your credit score and in most cases it improves your score due to lowering your utilization rate.

I highly doubt it.

The Chase pre-approval links are not available directly through their website and they tend to turn them off and on throughout the year. 

The Capital One Venture x and Capital One upgrade link is especially hard to find as well. 

I'm even finding new unreported links every week that have never been posted about. 

Not at all.

Pre-approvals are about 90% accurate for determining whether you'll be fully approved or not. 

Pre-approvals just require a soft credit pull which does NOT affect your credit score. You only receive a hard credit pull when you accept the credit card offer.

If you don't like your offer some reason then you can back out and it's like nothing ever happened.