Hi CEM
As you noted, the sign-up bonuses are where the best ROI comes from.
My everyday spend card is most often the most recent card I applied for, the one I'm currently trying to meet the minimum spend on.
When this doesn't apply, our everyday spend card depends on the purchase - we use the Sapphire Reserve for restaurants/uber/travel, the CapOne Venture when booking on hotels.com, the United card when booking United flights, the Marriott Bonvoy when staying at Marriott hotels, etc...
I also use the Chase Freedom card on the special quarterly categories (5 pts per $1), and in the US for generic spending I might use the Chase Freedom Unlimited as it earns 1.5 points per $1.
There are cards I have which I would never use for general everyday spending.
One example:
I have the IHG hotel credit card in my desk drawer. I pay the annual fee every year for the annual night certificate, so I spend $89 for a $150-$200 hotel stay.
That card currently has a signup bonus of 140,000 points after spending $3k.
To get that same number of points later, with just general spending, would require spending $140,000! 1 point per $1. NO THANKS!
But when we use the night certificate I'll pull that card out of the drawer and use it for food or general expenses at the hotel, as it earns 25 points per $1 at the hotel.
Make sense?
Cheers
Jeremy