I would start with the base game and see if you like it. It´s actually a very different gameplay compared to the Sims 4. Personally, I prefer the Sims 3, but I also like and play Sims 4.
You don´t need a gaming rig to run the game, I play it on a normal pc without any problems, but a dedicated graphic card sure helps with performance. Wouldn´t play it on a normal laptop (it nearly fried mine).
Highly recommend the Nraas mods, they help with all the annoying bugs the developers never bothered to fix.