I am from the 7DS team... and thank to say that our mod is excelent...
BUT
all the mod have his own value... no one is better that the other...
About 7DS, the base of the mod is called Solar sins... both are for sins 1.05... but if you wish use a more recent version of sins, you have a non official Solar sins for 1.1 at http://files.filefront.com/Solar+Sins+v20/;13149386;/fileinfo.html ... Solar sins is 7DS with the graphical effect, the new planets, the new bonus but without any new races...
About other mod, you have numerous one... need to see what your sins version is !!! Personaly, i like the stargate mod from Doylnick... great coding work and lately, the new models are coming to life... if yo are more about a lot of research, i remember a mod called something like "mad scientist"...
Seriously, you need to say more about what you seek in sins... some mod are more for little map, some other more for the long play... some for old version of sins, some for the last one... some are more graphical, some are more tactical... really the choice is too much huge for say what is the best for you without knowing what you wish...