I'll be speaking from my experience. And because you didn't supply information about yourself. Equips, pet and all.
Accessories, Altiverse Rings. Why? Both have AC for your damage, LK for your accuracy and blocking, HV for your dodging, HP for your ... HP. You may get ring with weak stat, but with two rings that has HP, LK, HV, AC, its all good stat for you.
Head. If you get lucky the Speech Balloon Head for head equip. No AC comp i think.
Face. Bloody Red Eye Patch. You can comp with LK and AC
Gun, generally any gun with more than 700 Gun AP. Then refine, I know refining is costly. Although Altiverse equips is really cheap in refining and comping, less than 50k. If it has slot, either comp with AC or LK.
Hat. Any hat with AC and LK
Set. If you can get Altiverse Set, that's good, it adds AC, LK, and HP as well. DA as well I think.
Inner-wear, I think you know which to get already. Do take a look at the Snow Hill inner-wear, it might interest you. You also have the tradable Koala shirt right now.
Pet, there are lots of free pets recently, im sure you have collected them (I have all character slot full so that I can collect all tiers)
Cape. Poppuri Cape,, the only ingame cape that I know of. Or the level 60 Cape Gift. just raise another character, get advance, get cape. repeat every month.
Accessories. I would still go with Altiverse Rings.
Head and Face. With good selection, you'll get HP, AC, LK, DP, MD, HV. little things add up you know. As for the level, maybe you want to get one first, then get the other one at level 250, i think the difference will be few AC. You can check the stats and compare that yourself
Cape. For your Cape, the permanent MyShop one is at Level 250. Which I say, if the sale is limited, you better get it first. You have two choice for the capes. The Power with 25AC 500 MD, 1000HP, 250 DP, and 12 HV. Or the Charm one with 13 AC 580 MD, 2037 HP, 250 DP and 44 HV. If you get the Altiverse rings, go with the Power one. Unless you want to stack lots of HP. You can try Gacha cape as well.
Innerwear. Collect the Bonus Egg I guess.
weapon. normal myshop weapon wont last long. Either see if you can have a good Gacha. or just get ingame weapon.
Hat. Ifrit's Helmet I think. But then, its better if you get Altiverse Helmet and Set.
Pet. the crystal pet. You have choice of Charm or Power Pet. with some differences as you may note yourself in comparing. I bought Titania for the DP, HP, AC, HV. but it was before the Altiverse comes out. Its your choice. And the usual LOLbox and Gacha Pet.
Your level is 191. The myshop head.face equips is at level 170, 190, 210, 230, 250 i think. See the difference in stats, and judge whether you want to wait until level 250 or you just bought the level 190. As for comping them, from my experience, and with the current 'working as intended compounding system', its better to get Nate's bottle rather than Myshop stones. Don't be lazy and go hunt those stones.
If you want to Solo the Chaos Tower, the magic stat is 300LK, or rather 207 x 1.45 (Lucky Seven Mastered). Only then you will be able to hit Floor 60th and 72nd bosses. Shield Breaker is the key in killing them quickly. Dont worry if you miss, just keep trying, because you only need 2 to 3 Shield Breaker to kill them. Shooting Spree and Berserk helps in killing as well as clearing summoned mobs. I only use Double Shot, Shooting Spree, Berserk, Lucky Seven. HP=12K, they miss a lot, and HV>100 really helps, small things add up.
Region boss accessory is good as well, but you know the trouble to get them. Its good that Bloody Red Eye Patchis tradable, and only 25M in Fantasia.
Lastly, Its just my advice for PVM. dont ask me about PVP, my Laptop can;t handle that. though my assumption is more HP, AC and LK. or rather lots of LK and AC, the glass cannon style. my gun currently is level 10 altiverse thorny rose gun with base AP of 1278( i think) max is 1400. Refined 4K++. I got it the second day Chaos Tower was released. Level 170 Myshop head and face, my level is 250. Gacha Cape, Rosalyna. snowhill innerwear, will switch to Egshop innerwear when i have enough eggs. Thorny Rose and Flash Bat altiverse rings. Pet is Titania Crystal. Thorny Rose Hat as well.