If you don't already have one, a cool mist humidifier running in his room will REALLY help. The first time my DD was congested, she was 13 months old and I ran out at midnight to a 24hr. pharmacy to buy one for her. It was way too loud, so I bought her the one that looks like a penquin (they have other animals) and it is very quite, easy to handle, etc. Everytime she gets sick, I run it constantly in her room. I also run it if she shows signs of dry skin, chapped lips, etc.
As for the congestion, I am no expert, but my pedi would probably take a wait and see approach, too. I would say to use saline drops with the suctioning, because saline kills any viruses living in there. But the absolute BEST thing that worked for my dd was a BREAST MILK spray up the nose and suctioning. That stuff is a wonder drug!! We used it everytime we flew on a plane or were around obviously sick people. It kills the 'bugs' and helps clear things up! It can be used on scrapes, too!! Anything that needs to be healed! Ok, back on track, use the humidifier, treat the fever only if it gets high, and maybe be prepared with some over the counter decongestant. Also, take him in the bathroom when you shower. (The steam will help.) If you hear a barking sound when he breaths or any signs of struggling to move air (wheezing, gasping, high pitched coughing, flared nostrils on inhalation, etc.) treat it with urgency. If he is having trouble with that sort of loud breathing, take him out in the cool air, that can sometimes calm his nasal passages and open the airway enough to get him to a doctor. I won't go into detail about something that he may not have, but just be prepared to call the doc if his symptoms worsen.
Don't forget to take care of yourself, too, because if he is sick, you are probably next. Wash your hands and his a lot! Keep everything sanitized, too. Those are my suggestions for treating him without drugging him.
Hope that helps!!
My best!!