UI illustration set for nature journaling app (iOS/Android)

Fieldnotes is a nature journaling app for iOS and Android. We need an illustration set for our onboarding screens, empty states, and feature highlights — around 12 illustrations total. Style: clean, naturalistic, slightly editorial. Not flat icon style. Should feel like field-guide art crossed with modern UI. Deliverables: SVG + PNG at 2× and 3×.