For Colombia the main risk is that you are sphered by a GP before becoming a GP yourself, which normally makes it difficult to keep a balanced budget and is likely to result in the loss of Panama to that GP, which you can't form Gran Colombia without. One tactic to use if you are is to make the state of Panama independent just before being placed in a GP's sphere, as a delaying tactic.
You need to become a GP before about 1865 - preferably late 1850s - and the only way I have been able to do it is prestige, as Colombia can't afford an enormous army or navy and industry will be insignificant for a while. So you should first research the first two aesthetics techs, then the first tech that increases your research points. After that, commerce and industry techs will probably be needed to keep on top of your budget. You should always research prestige-improving culture techs as soon as they become available, prioritizing aesthetics in particular. This may mean not researching anything for brief periods in order to dive in as soon as these research techs become available.
At the beginning maintain good relations with Brazil, who has a core in Amazonas. When these relations are sufficient declare war to make your neighbors your puppets, adding the 'humiliate' goal for prestige.
You only need Ecuador and Venezuela to form Gran Colombia, but it's fun to try and get most of Latin America puppeted. Start with smaller less powerful states and finish with Argentina and Brazil. If Brazil is allied with a GP decrease relations so that they declare war for Amazonas.
If up to it you may be able to move on to Mexico or even the CSA. I've never been able to do this but the best tactic is to wait until the US has diminished most of their brigades before declaring war.
Once Gran Colombia is formed you will finally be financially viable, but it is unlikely that you will ever have a planned economy or state capitalism unless you use national focus to encourage these parties actively.
