I have two female P. irminia. They're beautiful and feisty and I love them. That said, they aren't the most visible T in the world. Your set up looks pretty good for the size of spider you've got. As he/she grows, I would go with something a little taller, but don't go crazy with a huge container. I made that mistake with my first. I have her in a 12"x12"x18" Exoterra and it's just too much for her. She wanders around it from time to time, but she would do just as well or better in one of those tall micros. As for what your spider is doing right now? I can't say for sure. My suntigers have on occasion barricaded themselves in for weeks or months at a time. I assumed they were preparing to molt only to have them come out looking the same as before, just a little hungrier. He/she could be preparing for a molt or just getting over the stress of being rehoused. From the looks of her, I wouldn't worry about feeding her for quite a while. She'll be fine until she comes out searching or waiting for her cricket. Just keep the water dish full and try to keep the humidity up, but I've found that they are fairly resiliant little things. Keeping the cage wet to keep the humidity up and daily misting usually leads to fungus which is a real pain in the rear. Don't stress too much about the humidity. Mist maybe one or two times a week.
One more thing. I know that everybody says P. irminia and P. cambridgei are arboreal and I guess this is technically true, but they aren't arboreal in the same way the Avicularia are. I see where the OP (Storm76) replied to one of the comments about them being burrowers by saying that some burrow as slings but they move their homes higher as they grow. That may or may not be true in the wild, but in my experience, the opposite is true. I kept my slings in those little plastic craft cubes that alot of people seem to use with some substrate in the bottom and a piece of cork bark usually glued inside the top. My slings tended to spend most of their time on the cork bark, building tube webs on top of it. As they got larger, they began extending those tubes down the sides to the substrate. As they became, adults/sub-adults, I moved them into larger containers with more substrate and more vertical climbing space with a vertical piece of cork bark usually leaned securely from the substrate to a wall or corner near the top. In these new cages, my P. irminia immediately built her web retreat at the sheltered base of the cork bark and remained hidden there for several weeks, digging a hidden burrow under the substrate. Now she comes out sometimes 4 or 5 days a week. Sometimes she'll sit on the cage door while I'm trying to do maintenance and make things more difficult, but she's not like my Avics, always at the top of the cage and almost always visible. My P. cambridgei was similar. Same set ups as the P. irminia. She was even more fun. Taking crickets from my tongs, investigating every intrusion into her cage, even the occasional threat display or slap. She showed no fear. She showed no inclination to burrow, even when she grew to around 5" dls and I moved her to her large cage. Moving her was quite a battle...she even pulled my paint brush out of my hand. LOL! Then she went into premolt and dug a burrow. I didn't see her for several months. After she finally emerged, she was big and beautiful...7.5" and a yellowish dark gray, but her personality had changed. Now she's usually hiding in her burrow...she'll only come out during the day when she thinks its feeding time. I see her first thing in the morning when I first turn on the light, but she's usually gone by the time I get out of the shower. So what was my point again or was I just talking about my pets again? Oh, right, don't just assume that, because your little suntiger is considered an arboreal, you are going to see it climbing on the side of it's cage or on it's cork bark all the time. There will be lots of times when it's doing just what it's doing now and if you're like me, you'll be wondering, "Is something wrong?, Did I do something wrong?, Did I get the screwed up one? Should I try to help it?, Should I look and see if it's ok?". The answer to these questions is almost always no.
Anyway, I'm not sure if I answered any questions or just rambled on....or if anyone will even read it.