For new shaper owners I always suggest 3 cutters to start with
1) a 125mm diameter carbide rebate head for rebates, planing, bevelling and pattern copying?
2) an adjustable groover for grooves, bridle joints and tenons.
3) a 40 or 40/50mm Euroblock head with limiters for steel knives, which will handle most of your solid wood profiling
As you have a Felder, I presume you have a curve guard, I would add a few back bearing guide rings including a 125mm one
Regards, Rod
rodsheridan