I wanted to know if the measurement could be better, more accurate using INA219 or voltage/current sensors connected with ADCs? Also considering the time to implement both systems, which would give me more advantages?
Use the 1NA219, or any other IC that offers 'high-side' measurement.
To explain: current is measured by putting a small resistor in the battery line; say you have a 12V battery and it is feeding 1 amp, then if you use a 0.1 ohm resistor, one side of the resistor will be 12V, the other 11.9V. To measure these voltages with an ADC you have to use potential dividers on both voltages, maybe 5:1 so the voltages become 2.4 and 2.38 volts.
Note that you have reduced the difference between the two voltages, so will have lost a lot of accuracy in your measurement; also you've connected a potential divider across your battery which will waste some of its power.
High-side measurement gets round this problem by giving you the difference between the two resistor voltages, so is a lot easier to work with.
This is similar to the other question you asked. I'm not sure if you read the answer that I suggested in a comment to that question, but I do feel it also answers this question. By that, I mean if you define "better" as high accuracy and ease of integration, the INA260 is an excellent choice.
And FWIW: The primary difference between the INA219 and the INA260 is that the INA260 has the current-sensing resistor built into the chip. Unless you have some fairly unusual or extreme requirements, that makes the INA260 the clear choice for "better".