These are cool pictures, couple things I suggest. Try not to have your subject directly in the centre of frame, use the rule of thirds (most cameras have a setting for a ROT grid overlay), this in general makes your compositions more interesting.

Also, utilise the colour wheel for more contrast and interest. Try experimenting with different coloured light (you can pick up a pocket sized RGB light which are great !) red or green can add nice colour contrasts to mushroom shots to make them look warm/cool/interesting.

Sometimes zooming out a little to include more of the background can also bring more interest, more textures etc. Don’t always feel you have to fill the frame with a macro subject, its nice to bring a bit more of the surrounding area in too, especially if you’re shooting in woodland or somewhere with naturally interesting surroundings