A setup close to the wall is possible in principle, but we cannot offer bases with the recommended height of at least 1.40 metres. Stability at this height can only be guaranteed if the base plate is very large.
However, a base of roughly 1 x 1 metres is certainly not a pleasant sight. Perhaps your joiner will be able to make something that matches your room.
Otherwise, you should use direct emitters for the surround channels as well - the same models as for the front speakers is best.