Thinking about getting a new axolotl-Advice?

Hello all. I recently lost my beloved Falcor (my first Axolotl). I adopted him from someone who no longer wanted him. After many a good time together, he passed away at around 9 years of age on Thursday. So, after crying for 3 days straight, I am contemplating getting a new friend.
Now, most of my friends and family thought I spoiled him greatly, but if I get a new one, I want them to be as healthy and happy as they can be, and I am most certainly no expert.
I have cleaned out his tank, and am preparing to cycle it for a new kid. I have been researching aquatic plants, got new substrate, and will be getting an external canister filter shortly.
The reason for my post is this, Falcor was not very well taken care of for most of his life. His gills were tiny when I got him, and he frequently went to the surface to gulp air. Will having live plants help with ammonia levels, etc. and prevent these sorts of problems? Also, does having live plants raise the risk of fungus or illness at all? Falcor absolutely refused to be removed from his new home once I got him in there, and I fear the same with my next one so want to avoid illness at all costs.
Well, I guess that's about it, thanks for reading my post. And thanks in advance for any advice, or suggestions!

Falcor gulped air because he wasn't getting enough with his gills. Why his gills were small could be a number of reasons. But chances are having plants wouldn't have stopped him from gulping so much.

Plants are beneficial to have because they can help with water quality, and also increase oxygen in the water. There isn't any real 'danger' with plants, unless they start to decay, in which case they can really increase your ammonia levels.

Gulping isn't always an issue, or to do with water quality imho..

My axies gulp air to control bouyancy, they gulp to aid their swimming and then burp it out when they have had enough swimming about.

Of course they can swim without doing it, but my larger, 1 foot long heavyweight finds it easier with a bit of air. It is a learnt behaviour from my younger smaller axie with long fluffy gills.