Karin Markers is a really nice brand that you won't find in many stores. Here is her addition among gel pens. Otherwise, she has two models of brush pens that are really good, Brushmarker Pro and Pigment deco brush.
Decogel are classic gel pens with either pastel, glitter or metallic. Similar brand is Gelly Roll which are also really good pens. Pentel's Hybrid Dual Metallic are super lovely, they have a twist in that different shades are visible depending on the angle and light.