Questions from a future PCer

Due to an injury at work I am done with my career of 13 years. My plan is to get into Architecture being that I have some Auto CAD and Photoshop experience. I plan on building a PC for this reason. What kind of things should I be looking for to get the most out of my future pc? I plan on running auto cad and photoshop and I also wanted to dabble in some kind of 3D rendering for my walk throughs of houses. I also want to use the computer for some light gaming ( I.E Age of Empires, The Sims, and possibly some games on steam since I already have a few ) As for the budget I’m not too concerned about it but would like to stay around the 3k area. I have a drafting table that will be used as my main desk and I’ll be building a small rig to hold my art supplies, tower and monitor. I plan on mounting the monitor to a swivel mount on the rig.. what kind of monitor should I be looking for? I’d like something with a good black/color range and decent refresh rate but don’t want to go too crazy since I won’t be playing any high end games. Thank you in advance for your input and I’m extremely excited to join the Master Race with my new endeavor.