What due diligence should be expected for a seed investment from seed fund(s) and individuals?

I like to take a rule from the Steve jobs playbook and use simple circles... one larger than the other but no more than 2. your most immediate target (realistic reachable) and one of the "enemy" competitor company. or overall untapped market cap. **for this to be effective you must provide as accurate projections as possible** no bar graphs and as little or no text as possible... remember that a deck is a companion to the speaker... avoid bullet points and use the deck to entertain rather than educate... is not a class is a pitch. :)

AngelList is your best bet. Since you're asking the question, chances are you don't have a way to get introduced to these investors. The simple truth (like it or not) is the chances very low that you'll get a deal done without an introduction from someone they trust. AngelList can help with that, so can going to networking events. And finally, If you're the introverted developer type, you can also get their attention by just building something really cool on your own, followed by some serious traction. Arguably the best strategy of them all.

If you want information that matters in "Creative Financing Techniques" find a person with the experience/insight. Most of what is in books is dated. Many of the more creative methods are a function of current tax code and market factors (like QE).

The best time to raise capital for a startup is when you have a clear idea of what you want to do and a clear idea of how much money you need to get to a milestone that will set a higher value for your company. In general its better to bootstrap and do friends and family as long as you can, because the more mature and successful you are the better deal you will get from angels or VCs.

You are right that the range is wide. You need to figure what are good values to have for your category. Also, you can focus on the trend (is your DAU/MAU increasing vs decreasing after you make changes) even if benchmarking is tough. Unless your app is adding a huge number of users every day (which can skew DAU/MAU), you can trust the ratio as a good indication of how engaged your users are. For games, DAU/MAU of ~20-30% is considered to be pretty good. For social apps, like a messenger app, a successful one would have a DAU/MAU closer to 50%. In general most apps struggle to get to DAU/MAU of 20% or more. Make sure you have the right definition of who is an active user for your app, and get a good sense of what % of users are actually using your app every day. Happy to discuss what is a good benchmark for your specific app depending on what it does.