You can top the plants if they're getting too tall, that encourages them to put their energy into the fruit business.
Your greenhouse is similar to mine, with sides that give less light or block it. I assume E or W. My plants are always taller than the same varieties grown in other situations here in the same area, and my fruit are usually smaller than the average too. If you really want bigger fruit, pinching off blossoms to have fewer fruits per cluster will also help.
There are some tweaks I've read about, for getting fruits to set ie switching the plant from vegetative toward reproductive mode, but if your fruit are already set I think they don't apply...
Just on my observations, the fruit really pump up when relative humidity is a bit higher and temperature too. The sunny day when my greenhouse is open and cooled by a breeze is not the best day for fruit growth - it can be cloudy or raining and the greenhouse closed up but warm enough - over 70 F - and then the fruit growth is noticeable. AKMark pointed out the 60F night temperature as ideal, and I've noticed that too, the fruit get plumper overnight but not so much if the nights are closer to 50 F.