Don't get discouraged. This is a process and it can take awhile. It took me a good 6 months and a haircut before I started getting really consistent waves. It took about 4 months before it stopped looking so stringy and tangly. I'm going to make some suggestions below. I mean them in a helpful way, not a bossy know it all kind of way.
Yes to Carrots and the Shea Moisture lines are both available at drug stores like Walgreens and are a pretty good for sulfate/silicone free shampoo and conditioner. So if things don't start improving with my suggestions below, you might look at switching from Evercurl to one of those lines. Your might just not like the Evercurl line.
Try using the shampoo on your scalp only. Just put some on your fingertips and scrub/massage the heck out of your scalp. Then scrub it again as you rinse. This way your scalp gets clean without drying out or damaging the length of your hair. As long as you aren't using silicones (although if you see a silicone with PEG next to it - like PEG dimethicone, those are safe because they wash away in water), you shouldn't have any issues with buildup in your hair because the water will wash any product away. After a few weeks, you should notice your scalp getting less oily as it adjust to no sulfates. Oh, and stop using sulfate shampoo once per week. It just confuses your scalp. Sulfates strip your scalp of oil, so your scalp responds by producing more. I'm at a point now where I can easily go 5 days without washing my hair and it doesn't look greasy at all. It took me a year to get there, but I'm there. So, NO SULFATES except when you go get your hair trimmed by your stylist and there aren't any other options.
Your hair might look gross the next couple of weeks, but you'll be thankful later as your waves get nicer and stronger. Getting rid of sulfates was the #1 best thing I ever did for my hair. I thought my hair was straight too until I went sulfate free and started letting it air dry and noticed it was getting really wavy. That was about a year before I went CG and started actually trying to encourage my hair to wave.
The only other thing I noticed is that you said you continue scrunching your hair as it dries. DO NOT do that. Scrunch right after applying your product and then don't touch it until it's dry. Gel works by creating a crunchy cast around your hair so it maintains that shape as it dries. Then once your hair is actually dry, you can scrunch gently to break up the gel cast. This leaves you with soft hair that maintains the shape it dried in.
Hold off on using sea salt spray while you're figuring out your waves. The whole purpose of sea salt spray is to create beachy waves, which are really loose and kind of stringy. It can dry out your waves too. I've got some sea salt spray, but I only use it occasionally when I'm going for that kind of messy wave look.
You might also try pixie diffusing your hair. It can help set the gel more quickly so that your waves dry in a tighter wave pattern.
Here's some photos of my journey. The first one is what my hair looked like when I was 100% sulfate free, but not doing anything with my hair to encourage wave or curl or anything. I thought it was straight with some bumps here and there. The next photo shows what my hair looked like on day 1 of going CG, week 7, 6 months, and about a year later. The 3rd photo was taken yesterday. I was being lazy because i was planning on going to a bonfire later and knew I'd have to wash it again when I got home, so I used NO product at all. Just washed, conditioned, put in some leave in conditioner, scrunched and air dried. I was pretty impressed. I really didn't think I'd get that much wave without product to hold it in place... as you can see, it's changed a LOT over the past year and a half as it got more hydrated, trimmed up, and less processed.
Good luck! Stick with it, you'll get there eventually...
Hair Properties: 2A/2B, Medium-fine, Normal porosity, Normal elasticity, Medium density
Low Poo: DevaCare, Yes to Cucumbers
Rinse Out: DevaCare One Condition, Yes to Cucumbers
Cowash: Suave Naturals Lavender
Curl Cream: AG ReCoil, Organix Moroccan Oil Curl Cream
Gel/Mousse: AIF, AIA Curling Jelly, Sweet Elixirs Flax Seed Gel w/ Mag Sulfate added, DevaCurl Frizz Free Foam, Aquage Uplifting Foam
Protein: Spiral Solutions Protein Spray for daily use