https://stylebyemilyhenderson.com/blog/the-guide-to-a-hanging-a-good-gallery-wall

Love your art. I would put one of the bigger pieces over the fireplace. As the blog above says, gallery walls are hard to do right. It's going to be like putting together a puzzle. But, if you picked that art out you definitely have some design sense.

I would pick a space you want to fill and then play with the arrangements on the floor before I started hanging things.

I would hang the largest one 5" above the fireplace mantel. The 2 little tropical villages on the right would tuck into a spot in the kitchen. Frame and mat the two larger horizontal street scenes to match and stack them vertically left of the FP where you have the tree. The gap between them should be a hand's width and should be centered 5' above the floor. The green matted portrait could be interesting in the powder room or guest bath. The pastel one behind it needs a frame. It might look good in a special small spot by itself. The remaining 4 should be framed to match and grouped over a table on your large wall. Hang them one frame's width apart with the bottom frames 5" above the table (which should be 25% wider than the group of pictures. That's my opinion; I'm sure there'll be more options offered.