I think you answered your own question...What would you do if you brought home another bird and they didn't get along? If you even have to ask yourself that question then you shouldn't get another bird. Period. Because all that's going to happen is you'll have 2 birds that now BOTH need your attention, so you've just doubled your original problem...No Bueno.
***I have multiple birds, and as Laura said many people do and love it. However, that "rule' of "Only buy a second bird if YOU WANT THE SECOND BIRD, and NEVER buy a second bird for your first bird" has pretty much been made a 'rule" for a very good reason. I wanted a second a bird. So did Laura. And that's totally fine for us. But it's quite obvious that you do not want a second bird for yourself, so you've already answered the question for yourself. And it seems quite counterintuitive to bring home a second parrot when your issue and the only reason you're doing it in the first place is that you feel like you don't have enough time for your first bird, lol.
Here's the thing: Birds/Parrots form relationships/bonds with other birds in much the same way people do. They meet them and they form first-impressions, and over-time they form one of many different types of relationships with them. They might love them to death and bond very closely with each other, and if they are of the opposite sex (another thing you won't be able to know without having them both DNA-tested for gender) and they bond-closely they will no-doubt start breeding and laying eggs. They might like each other but not to the point of breeding or wanting to be with each other every minute of the day. They might simply tolerate each other being around without being aggressive, but not really like each other much. They might really dislike each other and not want much to do with each other at all, and have to be kept separated because little 'nips" happen when they're together...And yes, they might hate each other, be very jealous of each other over you and the rest of their "Flock" who live in the house, and they might be extremely aggressive and violent...And not only do you have absolutley NO WAY iof knowing what type of relationship any new bird will have with your current bird, but you also have to realize that the relationship between the two of them can also change over-time, just like relationships between people change, and you have to be ready at any time to have to put them into separate cages and even have to have a special routine/schedule where both of them have separate out-of-cage-time each day. So the bottom-line is that you must be prepared to have to spend equal time with 2 different birds separately for the next 30+ years...
****Something else that people thinking about "bringing home a friend for their current bird" don't EVER think about or take into consideration is the fact that if your current bird and the new bird bond very closely with one-another (especially if they are of the opposite sex), it's possible and quite common for both birds, including your current bird that you've been bonded with for a long, long time, to no longer want to have much of anything to do with you at all because they now have a Flock-member that is another bird, and they would rather be very closely bonded with another bird than with a person....It's very sad when this happens because it resulted from nothing other than a concerned parrot owner wanting to provide a "friend' for their bird that they love very much and are quite close with and bonded to, and all that ends-up happening is they end-up with basically a bonded-pair of birds that want nothing at all to do with people any longer, that cannot be handled any longer, that bite, and that just want to be with one another alone and unbothered...There are varying-degrees to which this happens, but typically there is a change in the dynamic between you and your current bird if they bond closely with the new bird closely, and it's not a good change in dynamic. So you need to also be prepared for this situation to develop over-time as well...
Bottom-line is that parrots are "Flock-Animals" that are extremely intelligent and extremely social, and when you make the decision to bring one into your home and your life, the idea should be that YOU are their friend, and that you and everyone else who lives in your home are going to be their "Flock". And typically parrots bond very closely with one particular person in the house, totally of their choosing for whatever reason (which there is no rhyme or reason to a lot of the time), and it appears that in your home and your "Flock", your Conure has chosen YOU as "his person" and is closely bonded with you. And if you are spending 5 hours a day with your bird on-average, that's pretty good and more than enough to keep your bird happy and healthy. YOU are his friend, and there is no reason why he would need another bird to be his friend too, unless something changes in the future where you can't spend very much time with him at all during the day.
It sounds like you love your bird very much and just want him to be as happy and healhty as possible,, and sometimes when we feel that strongly about our birds being happy, we make decisions that are not in their best-interest at all, and that end very badly. As long as your bird has a nice, large cage with lots of different types of toys (chewing, shredding, foraging, swinging/climbing, etc.) inside of it to entertain himself with, and as long as you try your best to let him out of his cage whenever you're at home, then there is no reason to bring home another bird right now when you don't at all seem like you want one. And if sometime in the future YOU decide that YOU want a second parrot in the house, but only because YOU want to add another bird to your Flock and as another companion for YOU, where you're certain that you'll have enough free time and desire to spend equal-time with each bird out of it's cage every day, even if they have to be separate because they don't get along, then that's totally fine. But only when YOU want another bird AS A COMPANION FOR YOU, NOT FOR YOUR CURRENT BIRD.
It sounds to me like you're doing just fine and you have a very happy little guy that is perfectly fine having you to himself for right now. There's nothing at all wrong with wanting to bring home another bird to add to your family, but not until you are personally ready for another one, and not until you yourself want one for you.
