Mahogany is not lighter than alder NO WAY. For metal Mahogany will work better. Mahogany will also have awarmer tone (not necssarily dark).
Hey devil where do you live? I honestly wont even bother to make a custom guitar out of Poplar. Poplar is nicew but it is mostly used for amking PROTOTYPES. ( get the message). Edromans website is nice and quite intresting... I cant say much abouth Indian MAhogany but I gues it should be ok., but not as good as Honuran mahogany.. Albertos will also offer you wood choices
John 8:32 Then you will know the truth, and the truth will set you free."