#1(top left) - too much uniteresting space on the right. bottom petal competes with COI (Centre of Interest). I would do just close up of main petal with some DOF (depth of Field) experiments.
#2 - i would turn camer more to the left since yellow like maples disturbs petal pattern.
#3 - too chaotic composition. COI is in the middle i guess and front flower competes with COI. Furthermore other flowers disturb COI as well. either DOF blur or change composition
#4 - I assume COI is in the middle right. low contrast. COI disappers with similar color of bush. close up would be better.
I always use simplicity and art of substraction. flower must have soul and must speak. otherwsie, i don't even bother to assemble photo equipment.
Browse Album :: 20100801 calendula officinalis Photo :: IGP2574 Browse Album :: 20100724 tropaeolum majus
few examples of my first flowers. JPEGs are rubbish, but it may be enough for some inspiration despite they are not best.