I'm currently bikeless and need a new bike that will have to serve multiple purposes including light/moderate touring, gravel/light off-road, and club rides/racing. I've been fooling around with some of the gear calculator sites to see if I can come up with something that works for all these applications. I should probably be okay with 25-30" low, so I've found what look like two options: 52/39/24 with 13/14/15/16/17/18/19/20/21/23 or 48/32/22 with 12/13/14/15/16/17/18/19/20/21.

I had been thinking more about road groups (105 level), but the 2nd option would require mountain equipment, so my questions are:

1. Is there anything inherently wrong/bad with the gearing ranges I've come up with?
2. To what extent can you mix road/mountain groups on the drivetrain - ie could I use a Shimano mountain crank with 105 shifters and derailleurs?
3. Can 105 derailleurs handle this gearing?
4. Neither the chainrings nor the cassettes are stock in either of my possible solutions and it looks really expensive to change these things - ie 105 crank is 50/39/30 and it looks like the cost to switch to 52 would almost buy me an Ultegra triple! Is there a cost effective way to do this?
5. Anything else I need to consider?