The lack of load versatility would turn me off for a "small" double rifle to be used for light game. Get the gun regulated for one load and that's it. You're stuck with it. It's also my understanding that doubles inherently have problems with anything but short range. A drilling makes more sense to me. Miss or mess up the rifle shot, you've still got two quick barrels of buckshot for backup if things get suddenly hairy.
Some good advice there.
I have a nice drilling in 16ga and 7x57R, not sure it would be my first choice for European driven boar even though your comment makes a lot of sense. My existing Blaser R8 may go to the front of the line in .308, .300 WM or even 9.3x62, I have the red dot and have shot it well in the past in .308 for European boar.
I have driven boar shoots planned for later this year in Croatia and Turkey maybe I need to shoot a few more times before making a final decision.
My current itch is for a medium caliber side by side double rifle with a red dot sight, typically shooting range is not too far, I'm looking for manageable recoil so I can shoot my 2 shots fairly quickly.
I passed up on a very nice Chapuis double rifle in 7x57R with a spare set of 20ga barrels over 35 years ago as I could not quite afford it at the time, 25 years ago I passed over on a Holland & Holland 7x57R double as I could not quite justify the cost to myself at the time, both were amazing fitting and handling double rifles, how I wish I could go back in life. Were they the most practical caliber and guns, probably not but they were both amazing guns. 7x57R is maybe a little light for driven boar, but still I might need a very nice double in this caliber to satisfy my old itch.
Now at 60 years old my decisions just need to make me happy, who knows maybe I'll buy a couple of medium doubles and have a little fun in life.
For a more practical solution I've been looking at the new Chapuis X4 side by side double in either 9.3x74R or .30-06. I like the idea of 30-06 which is typically regulated for a 180gn load but also has the ability to be regulated for other bullet weights. It comes scope mount ready and has a free floating right barrel allowing regulating adjustment. Lot of advantage for 30-06 with cost, bullet selection and availability of ammo and components.
Alternatively someone may have an amazing treasure buried away that they are willing to pass on or part with, I'm keeping my options open just for now. It's always exciting when you are on the hunt for a new gun.
I see a real problem coming in life, my son enjoyed his first Africa buffalo cow culling trip so much he wants us to go back and try a buffalo bull hunt, there may just be a large double in the family future, I think we call these good problems to have in life.