Fein would work fine. Heh, heh, heh.
There are some nice small blades by Bosch: Bosch OSC38F 3/8 in. x 1-1/4 in. BIM Flush Cut Blade
Tips for successfully using the Multimaster:
Fresh blades are key.
Hold the tool with a "combat grip", two handed. Be ready for the torque induced by the offset of the blade. Always work with the blade on the thumb side of your dominant hand, as it's easier to handle. If necessary, rotate the blade.
Start the cut by rocking the blade into wood, heel (the end closet to you) first.
Draw a shallow cut to use as a guide for your deeper plunge. Keep the blade tipped up along the direction of your cut.
Do the outline of what you're cutting first. You can then nibble out to the border.
As for other tools:
You can use carving knives to start or finish off smaller or more complicated shapes, leaving the power tool to hog out the majority.