One argument is that getting one new cat could give him a new friend while he is lonely. Another argument is that I should get two new cats (like 2 siblings) who will hang out with each other and won't bother him (on the other hand, groups of three never work for friendships and I would hate him to feel like the odd man out).

For anyone who has gone through this, what do you recommend? Which method (one new kitty or two) has worked out better for you?

Thank in advance for your advice.

If I do this, what is the best method to introduce new cat(s) into the house? We have had a number of guest dogs and guest cats visit for weekends during my cat's life and we have usually just brought them into the house and let them meet my kitty right away and soon afterwards they have coexisted peacefully.

I don't know if I should try a new method for bringing in any new kitties? I have heard things like put the new cat(s) in a seperate room and let them smell each other. I have heard things like exchange smelly blankets during this process that smell like each other so they can get used to each other's smells. I'd appreciate any tricks of the trade you recommend!

I always separate a new cat in a guest bedroom and use a screen door in place of the normal door so the cats can see and smell each other through the screen and get use to each other without a big confrontation. It works for me.

I would go with two more, but mostly because there are a lot of homeless cats out there, and if you're willing to take two, you should. I would go with one older cat (2+) and one kitten though, rather than two that are the same age to keep your old man from getting shut out.