tl;dr it's not a conspiracy, it's marketing and with some work you can turn it to your advantage

Two points:

(1) A data set that includes only you + your friend is not enough to be statistically significant (neither is a string of offers lasting 5 days)

(2) I think we have all figured out at this point that offers (all offers) are based on past history in some way.

The more interesting exercise I would suggest to you is to recruit players and build a database of what everyone's daily offers are and what their spending habits have been. If you get enough data you might be able to guess at what the algorithm is and use that to maximize/time your purchases. 

The terms Wheel of Fortune, getting "Lucky" and the ability to choose between 3 "different" discount chests, implies that there is some chance involved.  If the content of the three chests is the same and the outcome of the "wheel of fortune" is determined in advance then I think I am right to consider this deceitful. 

If you need more data to be convinced of this I think you should gather it.  I have over 130 days of playing experience so I have more data than what I recently noted but it is mostly stored in my subconscious. 

I can tell you that I have never received a 70% discount on reviving units when I had champions or raiders to revive... is that by chance or by design?  Does the game record that I eventually revive those units after 7 days of waiting and therefore never offers the discount in the meantime?

I don't know if there is different occurrence based on your spending on wheel, but for sure there is different base chance to get lets say champs than lets say resource pack discounts, probably 50 times less likely, same with towers and so on. some common thing will be there often, it can be very random sometimes u might get 3 times in row great discount, but its very low probability.

if on other hand certain items have like 10 times higher chance to show up, then you should be statistically see them 10 times as much on average:)

I am certain that the Wheel is totally random.. I get good discounts on fortifications and such even though I have been maxed out long time ago.

I am also certain that the Bank offers are indeed based on past history -as mentioned by TLS- because for over a month now the only offers I have are for $330 and $180.

Like Lekkerdje said, "if u wait long enough and don't spend then good offers come back"! 

Some, just don't have luck to get that what they want for discount.. lol

I worship the gods all day Archons,

Yeah, same here, I'm going on getting discounts for fortifications that have been all upgraded to level 5 like 1 1/2 year ago... ^^ LOL

Or for those totally useless relocation pools... :(