We aim at exploring the ground state of new Cu2+ S=1/2 kagome compounds, isomorphic to the now-celebrated Herbertsmithite, namely CdCu3(OH)6Cl2 and MgCu3(OH)6Cl2. Due to the different ionic radii, we expect (1) that changes of the unit cell parameters will modify significantly the antiferromagnetic coupling and the Dzyaloshinski-Moriya interaction which are likely to drive the nature of the ground state, a question that is still deeply debated (2) to reduce the tendency to intersite mixing. Further, we propose to draw the phase diagram of the related families of compounds AxCu4-x(OH)6Cl2, A=Cd or Mg. The comparison of the Zn, Cd and Mg based atacamite will help to characterize the weak 3D couplings at play and which stabilize 3D order. In the same trend of ideas, we propose to investigate Haydeeite (the Mg analogue of the S=1/2 kapellasite) which shows a more pronounced 2D character.