A glimpse of what's in progress...
Again I'm a little surprised by how I've been able to keep the size down more than I expected.
My thinking behind this is that while sizable on the outside this craft is rather cramped on the inside and suitable for a complement of perhaps three personnel. This heavy auxiliary or "heavy lander" is meant for surveying worlds and anomalies with extreme conditions. It's sturdily built with enhanced shielding and structure. It has a powerful antigrav system as well as impulse engines in tandem with low warp capability. The nose or forward section of the craft is brimming with a variety of sensor arrays and scientific analysis equipment. A rough analogy of this vessel would be a space going version of a deep sea submersible. It's mission profiles are primarily of limited range and duration due mostly to its lack of support systems for the small crew for extended periods.
Small note: if it had been available to them this craft might have been a better choice of vehicle to explore the Murasaki 312 phenomena in "The Galileo Seven."
Still, as we saw in "Mudd's Passion" it doesn't do well with oversized alien dinosaurs.