Hi chili,
It looks to me like the first four you have there might be bluer in acidic soil, but the Blue Bunny shouldn't need it. We don't have acidic soil here, but I've found that I can raise acidity just enough by top-dressing with compost, pine fines and/or shredded oak leaves. I'd say just go ahead and plant them first, mulch them well with any of the above, and let them go ahead and get growing for you. You can always fiddle around with color changes later.
As to your other question...on which side of the wall are your old hydrangeas planted? If it's south or west they may need a really thick layer of compost, mulch or some under-plantings. They may be getting too hot and dry to bloom well.
