Lager brearings are for cranks that have been reground due to scoring you dont run them as an upgrade as such, it just makes a reground crank sit as it should. As for rods etc its all personal choice, i have custom rods from an american hotrod builder, others use lesser known brands to great effect and the masses use popular tried and known brands but in essance its what you are happy to use.
Athena are shit hot! I've only read one thread on issues with them and im fairly sure its a warped block or head not the gasket. As they manufacture gaskets for ferrari and moto gp super bikes id say they know their stuff, i rate them highly.
Pistons again personal, i use ridiculosly sized pistons but commonly 74.5 is a sensible option as its only mildly bigger than stock so gives plenty of bore thikness.
All that said a blown head is a bit extreem a reason for a full forge build if you have shows to attend, id just bung oem bolts and gasket in and forge after show season imo.