Exchange cylinder head seal – what risks?

OMEGA B CARAVAN 3.0 MV6, Built 1996, 219000 TKM: My cylinder head gaskets will be changed in the next few days, as the old ones look like a Swiss cheese (rather worse). What are the risks after the installation of the new cylinder head gaskets, since then the “pressure conditions” should be optimal again? Should I consider any “drive-in instructions” in the first time (if yes, how long?)? Of course, all other gaskets in the engine are also replaced (Ve Ntil cover seal, valve shaft seals, water pump seal etc. etc.). Exhaust valves are also exchanged, as 2 pcs. are “platt”. Exhaust manifolds are also exchanged including seals (due to “obligatory cracks” in the same…). Teeth belts (including all necessary) are also exchanged. Thanks in advance for opinions, suggestions, useful information. Greeting MV6Streetmachine