When learning if you have a choice between South Texas (South Padre and Corpus) and the West coast there really is no question IMO: you should go to Texas. I have lived and kited in both. South Texas is much easier and more user friendly for learning than anywhere else in the country (except the Outer Banks, NC which has almost identical conditions for learning). You will learn much faster in these places than others. What they have
1) Miles of shallow water with soft sand bottom. This is the biggest factor for making learning easy and pleasant. There is a huge comfort level between learning in waist deep water than overhead.
2) Easy and unobstructed launch and landing locations. This is most critical time in kiting where bad things can happen. Having a wide open clear area makes things way easier, safer, and more comfortable. The video about Sherman shows how limited and sketchy the launch is. There are great places in the world to kite, but if you get blown down wind you may be in a bad situation where you cannot get back in or land your kite. When you are learning you will be ending up downwind. Many places now a day have boat or jet ski assist where they follow you, but it is nice and usually cheaper not to need it.
3) Uncrowded. Nothing scarier and potentially dangerous than learning around other people. Places with limited access funnel everyone into one area. South Texas has a lot of locations with a lot of room
4) Wind Direction. For safety you need side-on or side shore winds. Too offshore and the shore may block the wind causing a shadow, but worse if something goes wrong you are blowing away from shore and safety. Too onshore forces you against the shore and produces the other danger of getting launched on to shore. Someone suggested Pismo, CA which is a fun place to ride, but it is almost dead onshore making it tricky for beginners. South Texas has favorable wind direction.
5) Clean consistent wind. This may be the second most important factor for ease and safety of learning. Places like the Gorge are very wind and very consistent, but can be super gusty making it challenging for even advanced kiters. In South Texas the wind is extremely consistent. Also for learning you want the wind to be relatively strong (upper teens to mid 20s). This may seem counter-intuitive, but it is actually much easier to learn when powered up on smaller kites. Learning on big kites in light wind is hard.
6) Warm water and air. Learning you spend a lot of time in the water. It is definitely a much more pleasant experience to be comfortable. The Texas season is obviously really long. One con is that summer in South Texas is not for the faint at heart. Coming from Denver you may feel you entered a sauna.
7) Flat water and current. Obviously much easier to learn in a place that is nice and flat without waves or chop. If you are in a river or moving water like the Gorge or places in the SF bay you have another issue to contend with.
8.) Wind Frequency. Obviously want to go to a place the blows every day. South Texas is pretty frequent, but not every day, so may need to look at the weather or call ahead. Places like Sherman, the Gorge, and California coast can be extremely frequent during the season and blow almost every day.
As already stated if you can get to Brownsville (BRO) you are 30 minutes to South Padre Island. Corpus Christi (CRP) is about 20-30 minutes to spots. If you have a weekend and you are in San Antonio (SAT) then it is 2 hrs to Corpus. If the East Coast is an option than Norfolk, New Port News, Richmond, and Raleigh but you around 2 hrs to OBX for a longer trip.
Once you learn, then the West Coast a good option, especially the SF bay area. You have several large airports in the vicinity and very consistent winds all summer. San Fran, Oakland, and San Jose are very close to kite spots. South Texas culture (which I dig), may not be your scene, and the Bay Area and central Cali coast are beautiful with lots to do. I do not know how lesson coasts compare, but for other things South Texas is a pretty cheap place and the Bay Area is not. Traffic may be an issue to consider because the Bay Area can have some pretty significant traffic. Final thing to consider is the Kite Season. Windy places may not have favorable winds all year. So where to go in Feb is different from August.