Plant Environment Matters
For your little plant friend to be happy, you need to find the ideal place for it to live its life (keeping in mind that that location may need to change for seasonality). A lot of plants don't like to be moved from their happy place, so it's sort of a race to find that sweet spot, but with a lot of trial and error. There are two main criteria in searching for indoor plant placement: Light and airflow. (I guess there are really three, because temperature swings can cause havoc as well, but both light and airflow play a role in temperature, so you're kind of already covered.)
Light
Many succulents like "6-8 hours of natural, indirect light." Don't we all? But sadly, this usually isn't available. So what do you do? Often, especially if you have a lot of plants, you simply buy grow lights to supplement. There are hundreds of varieties of grow lights, and you almost can't get one that is wrong, so just go searching for the size and specs that best fit your space, budget, and needs. But just like low light can be a problem, so can too much direct sunlight be. If you've found the perfect window for your little dude but feel there's too much light, consider backing him a bit more into the room with a plant stand or even a hanging plant holder to limit his exposure. I have heard of people using mirrors to bounce or direct light further into a room. I've never tried it, but it sounds interesting. If you try it, I'd just caution that you be careful not to create a laser-beam effect.
Airflow
Another thing to consider that often gets overlooked is airflow. While many houseplants actually like a little breeze around to strengthen them, some don't handle it well. So try not to place your new plants in the path of a fan, AC vent, or a heater to avoid overly drying the little dude out, varying his temperature and humidity too much, or even blowing tender leaves off their stems.
The Sweet Spot
Once you find your plant's happiest place, then you can start paying attention to its other needs, like how well it plays with other plants. Some plants need their space, and unfortunately, their sweet spot might also be other plants' sweet spot. Careful not to crowd them as they share that space. You can create a beautiful little scene with other plants of differing heights, textures, and colors but with the same light and watering requirements. Consider using shelf risers, plant stands, and hanging plant holders to better share areas.