Nice way to avoid mowing.

I like the pavers but think they are set too far apart from each other. I also think a few hostas or other shade lovers planted around the tree would soften the area.

Align the stepping stones with patio to extend the patio. Plant low growing evergreen shrubs in the area by the tree and the corner. Pay attention to how wide the shrubs get and don't over plant. Mulch. You can add additional plants later if you like. Search Houzz for stepping stones for ideas.

Move the pavers closer together. Plant a small tree by the fence and a ground cover where the mulch/pavers are. Add a few pots with colorful flowers. Save up to have a landscaping plan drawn up. It will be worth every penny to have a long term step by step plan.

Grass!!!!!!!!!!!!! or ground cover, remove the pavers. I have had the stone experience, not good. Plant some hosta, etc in the area in front of wall. Pots and plants on existing patio.