You definitely need to find another jeweller then! Tbh the CAD modelling is not something he does every single time, only for super complicated designs. But he does spend ages on the sketching etc. for every piece, makes wax casts, when making anything complicated/big/expensive he allows you to try on the "rough" (like the metal shell, before polishing/dipping/putting in the stones) to make sure it sits right. I think its terrible that the second guy was rude to you! At the end of the day, you are a customer spending a large amount of money on something very precious to you and if you're not happy and you're polite/reasonable in your concerns, he should be making things right for you. Even if he thought you were unreasonable, there's a nice way of telling someone that.
Definitely don't go to this person. He doesn't deserve your business. The good thing is that with gold and diamond, you can remake it as much as you like (within reason) so if you find someone else he/she can take your ring and remodel it to fix the issues you have with it. I'm afraid I don't really know how to find a good jeweller, I just go to the one who my mom goes to, but I know she found him through a referral. He was quite new when she found him so his prices were extremely reasonable, and he was recommended to her by a friend. The first few times she bought something he already had that she liked, after checking to see the quality was up to her fairly exacting standards. Then she gave him something quite easy to remodel as per a design she had thought of. When he passed that test also she started giving him more complex stuff, and built a relationship with him that meant that she could put him through the wringer for a fairly cheap bracelet because he knew he would be the one also making my sisters' wedding jewellery.
This jeweller is worth his weight in gold (no pun intended!). But then this jeweller knows he has good returning custom from you and your family I guess. I wish I knew a jeweller as flexible and talented. Referrals are not very likely given that people aren’t so into jewellery where I live.
Another thing is that the staff at this jeweller told me not to reset my diamond and platinum ring (a family ring) because here’s a fish the diamond could smash. I have literally never heard this before! You’re absolutely right, I should never go there again.