Coming from a previous Mercruiser/Bravo... my current Volvo Penta pump hanging off the crank pulley sure is a nice change.
Two hose clamps and 4 small 8mm headed bolts easily removed with a 1/4" ratchet... and the pump is on my workbench.
Swap-in a new impeller and back together in less than 15 minutes.

Not sure I would trust an electric pump. I'd probably cut-in a thru-hull fitting before I tried an electric unit. There has to be some benefit to that over pulling water all the way from the drive.

The only problem i see with going electric is debris going through the pump. The "advantage" we have now is the rubber vein impeller can somewhat deform or bend with some debris and avoid potential damage with "stuff" passing through it.
Most liquid pumps are going to be a Roller vein, or Turbine, or centrifugal style impeller style....get something going through the pump and it clogs or breaks stuff.....then good luck trying to potentially fix it on the water.....ive taken a raw water pump apart while floating and changed impeller and got back under way....and a spare impeller and/or belt is still cheaper and lighter then a spare electric pump :)

so true. I’ve had debris shred the impeller before. I always keep a couple with me when boating. I’ll stick with the mechanical pump due to cost. It’s a pain to get to in my hull but still doable.

After changing the raw water impellers on my packed in too tight twin Bravos a few weeks ago I got the cut up arms to show for it.
Next boat gets outboards. So sick of this inboard crap. Actually, if I skip the 'next boat', I hope to go strait to my Great Loop Boat.

I also like the idea of electric raw water pumps for mounting them wherever you want, but the benefits are probably not worth the effort involved. But if someone does build some, I do think it would be pretty cool.

I see a electric raw water pump as seriously flawed. For sake of discussion lets make up some imaginary numbers, lets say engine needs 100,000 btus of heat removal at idle and 1, 000,000 at wot. Lets say 5 gpm will have enough cooling to hold temp at 140 at idle so theoretically you need 50 GPM at wot. With crank/belt driven water pump the flow of pump goes up proportionately with RPMS, a electric one wont. So, for the electric one to work as a raw water pump will literally have to flow as much water as engine needs at wot ALL THE TIME unless its put on some kinda controller to match temp/ load or complex temperature base bypass valve. My buddy polebarn john has a saying for stuff like this : "Sounds like a bunch of hocus , pocus , california romance **** to me", lmao. We do come here to throw ideas around, I envision problems getting enough flow at wot and havoing too much flow at idle. part throttle. Then keep in mind, it still needs power to turn so alternator is gonna work harder.

Truth be told i have thought about this about 15yrs ago...the only version i see potentially working would be a centrifugal style pump with a macerator style blades to chop up anything "soft" that may pass thorough it. It would need to have some sloppy internal clearances too. As Articfriends pointed out easiest would need to be RPM controlled...easiest way to do that is by engine rpm. But if you wanted to go electric, the pump would need to be sized for proper cooling at idle and be able to supply enough flow up to a certain engine rpm....after that point the boat should be going fast enough to ram enough water through the system to keep itself cool and overtake the pump...hence the sloppy internals.
I know that a boats speed will keep the motor cool since i once fried an impeller and didn't have a spare onboard...so i took the guts out and took off the belt. Fired up the second motor and started going...once the boat got enough speed that it was plowing but cant get up on plane i kicked on the second motor and jammed it in gear and too off.....motor with no impeller stayed cool the entire time i was on plane :)

On a side note....I deal with marine AC guys almost daily since they use our pumps on the AC systems. The industry "usually" uses 1gpm for every 3k BTU's.
No idea what a motor puts out BTU wise but having some fun with Arcticfriends numbers you would need about 33gpm at idle and 333gpm at WOT lol :D