Your best bet would be to start banging an account manager at a logistics company that handles freight containers on ships if you want to get your stuff through to EU from outside. You need somebody who works logistics for import/export.
1) New accounts renting a container always get customs check randomly for first 1-2 years.
2) There are certain import numbers for items that are more likely to get your package "revised", like anything concerning machinery for example
3) Best bet would be to get your package through customs at such a company, get advised what number to put on your package and get your package through customs along with their smaller packages (multiple companies shipping smaller cargo get put into one container together). Obviously you would need a company for this and not your own.
4) Packages can still be searched randomly, even small cargo items from established companies, but at big ports it's like 1% and they focus on narcotics.