In 1., “even so” means “even if this is true” or “however”. It’s perfectly good and common usage here. 2. You could hear all three but “about” is very much the best. 3. Again, you can use either, but “for” would be more common. (In the US, we’d use “toward” rather than “towards”.

'Even so' means 'nonetheless'. https://www.collinsdictionary.com/dictionary/english/even-so What you need here is a word like 'therefore' or 'consequently' which supports your position rather than contradicts it. Also, your sentences are too long. Generally, in English, we limit a sentence to one or two subjects at the most. Here are my corrections. Notice that the first sentence uses the subjunctive because of the word 'recommends'. Third, the firm recommends its client invest in Consolidated Industries under the assumption that oil will still be the major heating fuel for many years, However, we cannot be sure of this. Therefore, it is too risky to invest in a company solely because its major business operations are the retail sale of home heating oil. Other aspects of the company should be examined before investing, for example, its revenue, costs, management efficiency, etc. in order to to determine whether the company is worth investing in or not.

1. ??????? I am not sure what your question is? The paragraph with 'even so' is correct. 2. He did not provide detailed information on how this data was collected. 3. The two factories might have different standards for on-the-job training.

Not sure what your question is, but there are several problems with the text.