You've simplified the issue to mere exchange or variance of bases. The occurence of new functions and their fixation is much more complicated.
Isn't a function a result of the arrangement of bases?
1- Are such variances when multiplied indicative of large-scale change?
As per the common definition of evolution, it is merely measured as a change in the allele percentage of a population. An example of this is a population of people having 5% red hair and over a decade having 9% red hair.
I wasn't referring to simple change in the proportions of population that have a particular hair colour, or any feature really. I'm referring to new genetic sequences that occur through the mechanisms of microevolution.
Another example can be the occurrence of citrate consuming ability of bacteria outside of the normal citrate consuming conditions for that bacteria... Would the ability to consume citrate unhindered lead to large-scale structural change? Nope... (Ironic since this example is used as evidence of evolution).
By structural change you mean a change in morphology, instead of a change in molecular function I assume? I would have thought that a change in morphology would also be governed by genetic sequences, and would be subject to selection. Do you believe they're not governed by genetic sequences or subject to natural selection?
2- The second issue is the requirement for each change to be beneficial. As has been mentioned by others previously, whilst changes happen and are beneficial under certain specific conditions the overall fitness of the organism is impeded.
I understand this is your position. We are discussing this on the other thread so there's no need to repeat ourselves here.
3- Observed limitation of change
What are the observed limitations of change?
4- The fourth issue is oscillating change. Studies done with Darwin's finches mentions that the beak % for the population changed when a drought affected the population. However when the drought passed the population went back to the original % meaning no net change was observed. These results fit with the Creationist account in that God created organisms with an inbuilt capacity to adapt to a changing environment.
Again, I'm not referring to the proportion of the population with an already existing feature. I'm talking about new genetic sequences. Regardless, if the environment doesn't return to its ancestor's environment then wouldn't the changes not revert?
5- Environment as the driver of evolutionary change. Considering the ever-changing nature of the environment there could not be constant change to allow for the fixation of a trait.
I'm not sure what you mean here. Can you please give an example.
That is what this thread is for, no new thread is needed.
I disagree. These are all very complicated topics. If a new person comes to browse this forum for these topics it would easiest for them if they can find threads dedicated to these specific topics, rather than browsing through tangental topics on the off chance they'll be discussed there. Would you like me to create a new thread for each of these topics?