If you're not overly worried about endemics and are interested in more economical routes you could consider the south of the country. Narino and Putumayo departments have several SUPERB reserves, lodges, birding trails etc. that can be done for a pretty reasonable price. You could fly into Tumaco, spend a day birding the pacific lowlands, a few days on the pacific slope at La Planada and Rio Nambi reserves, head into the highlands near Sibundoy (Laguna La Cocha, Paramo Bordoncillo) then spend a week or so on the east slope/foothills around Mocoa, Isla Escondida lodge (incredible new reserve!), Finca El Escondite. If time permits you could even fly out to Puerto Leguizamo for some Amazon proper - River Dolphins as well as heaps of great birds. Alternately, you could head into the upper Magdalena Valley to the El Encanto Lodge and the area around Palestina/Pitalito for a couple very restricted endemics like Dusky-headed Brushfinch.
Other top notch areas include Puerto Inirida (4-5 days) and the Cali area (good for a week or so).
Below are trip reports I've made for South Colombia and Puerto Inirida.
Feel free to shoot me an email at averybartelsAThotmail.com if you want any additional info re sites, local guides, general Colombia Q's. I've spent a cumulative ~2 years in Colombia over 9-10 trips so I know pretty much all the areas and most of the guides.
The birthday happened and she was quite pleased that her main present was a promise of some travel at an unspecified date (plus a copy of the field guide, when it's published).
We talked about a suitable time to travel to Colombia and came up with the idea of December 2022 and wondered if a trip over Xmas and New Year might be feasible, on the basis that she would be able to use the public holidays to reduce the drain on her limited leave allowance (and perhaps use days from both the 2022 and 2023 leave years. We will certainly engage some guides/join tours when in Colombia but will want to do some of it for outselves and I wonder have any visiting birders stayed during the Xmas period? I would imagine that most guides will want a few days off, so any suggestions of places/areas/hotels to stay, where we can at least guarantee to get properly fed on Christmas Day? I'm thinking somewhere coastal might be nice. This might be a better question for TripAdvisor but I thought I'd try here first because contributors will be able to answer from a birdy perspective.