What is your budget? Do you have kids? Do you entertain families, or just adults?

I think one or two table and chair sets are a good start, and since you seem to get a lot of sun I would add some umbrellas, too.

A swing set for kids? A rock-climbing wall? A pool, if you have that kind of a budget. Here are some ideas:

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I would say $15,000 - Thought about long porch on first picture.

Beautiful space to landscape! I would go with a large patio area for sitting and dining. Most people go with covered area directly off the back of the building in case of rain, but seriously how many eat outside in wet, muggy weather. Not many. I would situate a covered shelter away from the house to create more of a series of outdoor rooms. Also, install plants along the foundation keeping mature size in mind and with additional space behind to prevent bugs and increase air flow. Create a flow with some varied heights of trees and shrubs to create interest. Not sure if you want a cooking area, but it can be done to look like a built in and you simply use a roll in grilltop. Keep lines curved for a softer look and straight for a more formal look. Choose flowers that you can divide and multi season interest. I prefer low tolerant ones for times of drought, but if you don't mind water more often and a big bill, then the skies the limit with what to plant. When installing plants, always makes sure to create large expanses of similar plants so care is easier and less distracting. I think a more modern garden would look incredible in this space with long simple benches with cushions, possibly a fire pit even with a gas setup. If you want a drawing contact me at cynkloeter@gmail.com.

We entertain families and have lots of parties. We have a ranch so the view is great off the backyard. I would like a firepit and outdoor kitchen of some sort

How about framing the view you have with plants? No need to cut it off with greenery. Outdoor fire pit would require it to be place 25+ feet away from a home. Check before building with planning dept or whoever takes care of permits. It can be created from simple stacked cinder blocked, cement coated to look like stone or kept more modern and smooth coated. Rectangular are cheaper to build and can be combined with planters filled with rocks and succulents.

Check out this oasis by Jamie Durie. Love the water! Seems extravagant, but not as hard to do as you think. However, get landscaper to do it and well over budget. Just had to share as I find it has a peaceful feel about it.
http://www.dailyherald.com/article/20120715/entlife/707159991/photos/EP5/

Google modern landscape idea and you will find many that have decked areas, water features, firepits, etc. The idea is to have areas to walk and look at scenery, sit and have a dinner or party, light up at night so it just amazing paradise at night, and allows you privacy to some degree. I can help more but heading to bed.
Good night.