The Holga was more of a relief thing, where it was nice to not carry a light meter, set distance approximiately, and simply just wing it all along. The lens for the 5x7, well it was inexpensive, so I continue using it. The Summitar - I usually shoot it at f/4 of smaller, and only use it wide open up close for portraits, mostly because I like the depth of field at that aperture, and disregard what goes on in the background... To me it just isn't important to break new grounds with new lenses or equipment. It's just about finding something that works for me, and then continue using it, and simply just try to get better at photographing what I want to convey, and to show that well in the print.
In ten years, I might be the one exploring new lenses. Who knows?