i would group your three 'stumpy' looking upright wood pieces on the right hand side, coming out from the corner. the other skinnier piece of wood i would turn horizontally and have it come from the centre rear of the tank angling towards the left front corner (but have it be elevated above the substrate - the short arm of the wood in the centre rear of tank, comes up and then the long arm goes towards left front corner - make any sense to you? lol). plant about half your stem plants in amongst the three 'stumpy' woods, put 1/4 of stem plants in the back left corner (spread out a little bit), and get some crypts to fill in the middle between the stumpy woods and the other wood that is angled towards left front corner. put leftover 1/4 of stem plants along the back wall of the tank wherever you see empty areas.
the smaller of the rocks i would place in front of the stumpy woods and plant a few java ferns in between the nooks n crannies.