I dont know about the crank, id say adapting it to an EA82 would cost more than it would be worth. I am assuming you want it for more stroke? but the crank is only part of stroking out the motor, you have to adjust piston or crank arms as well to keep the piston from raising too high in the block. I dont know if it may work with just the crank for sure though.
if you want to add the turbo you need a proper computer out of the correct subaru, or spend money on a stand alone and laptop. megasquirt is probably the best solution if your going to have to aquire the ECU anyway.
high compression and boost is possible but it will take a lot more than adding pistons and a turbo. again the motor cant handle it in stock form, and will require some fairly major upgrades. you will have to upgrade the injectors at least, and likely the entire fuel system so that it can keep up with the fuel demands of a motor. the fuel system is rated for HP, and subaru didnt leave much if any expansion capacity in their fuel systems. you probably dont need a cats meow fuel pump due to the low HP in general, but you will likely have to get at least a higher output stock one from another vehicle, get new injectors, and possibly run new fuel line.
the pressures in the combustion chamber can only take so much, when subaru added boost they dropped the compression ratio to 7.7/1. this made room for the extra air and fuel that the turbo added. adding that compression back is no different than putting on a bigger turbo (as far as dependability goes). if you go all the way to 9.5 with spfi pistons, I dont know that I wouldnt run less boost than stock. in my mind its a better system, to run less boost and higher compression, simply because it would give more power in town when your not on the boost a lot, but you will need to make sure your headgaskets are in top shape. id be prepaired to replace them more often as well.
the heads really are the beating heart of any motor. its basically just a big air pump, the only real way to make more power is to pump more through it. you can force more air/fuel into the chamber with forced induction or increase the amount of volume that the cylinder pulls. thats why bigger motors stroke out, it allows them to push more through without stressing the components and running aviation fuel. even a large motor starts with the heads though, thats one reason you get 3 different 351 ford motors that all have vastly different outputs.
an EA82 is generally cut out from the most productive changes since there are no viable ways to increase volume significantly, and they cant take the heat and pressure from what most would consider minor forced induction.
this really has been worked out. experimentation isnt bad, you can and should find out things for yourself, but there have been numerous people, including some that have posted here, that have actual motor building experience, work in machine shop, etc, that have brought real science to this idea. the heads have been inspected, modified, and found lacking, people have run big turbos, independant fuel mgmt, high compression, superchargers and the list goes on. botom line is that you can have a reliable 110 hp car, a fairly reliable 125 hp car if you spend another 1k, or a suspect 135+ hp car for a few thousand dollars. or you can have a very reliable 165 hp car for $1k - $1500 with a motor swap. if you really want some decent advise you will have to start with a budget number, since money is the only real obstacle.