6 Weeks Solo Backpacking Colombia Itinerary

Hello guys, I will be backpacking Colombia from mid january until the beginning of march. I came up with this Itinerary and consider it realistic. I would be interested in your thoughts on this:

• 3-4 Days Bogota. Arrival in Bogota 19:35 on Friday, planning to stay there the weekend.
• 1-2 Days Tatcoa Desert
• 1 Day San Augustin
• 1 Day Popayan
• 4 Days Cali
• 4 Days Pacific Coast (Buenaventura Area, most likely Uramba Bahia Malaga National Park)
• 4 Days Medellin
• 9 Days greater Santa Marta Area including National Parks, Beaches and so on (Getting there by Plane from Medellin to Riohacha)
• 3-4 Days Carnival in Barranquilla
• 6 Days Cartagena including surrounding Islands
• Flight from Cartagena back to Bogota

I would be interested to know if the time frames are somewhat realistic. Do you have any concerns about safety? Are the transits realistic? Also happy to hear about destinations that should be seen.

I appreciate any suggestions and tips you may have. Thanks!