'I AM AVAILABLE'
Hello,
Answers for question that you have mentioned in project brief.
1 - Html coding standard should meet W3C Markup Validation. There is online tool which tells that html is validated or not according to W3C Markup Validation.
2 - A website developer can only do on-page seo because offline seo is very time consuming. I can do on page seo. There are couple of things which are responsible for on-page seo, like title tage, meta tags, keyword density, url structure, heading tag, content, image alt tag. etc.
3 - I make website which is easy to use and can extend its development. I usually make website with codeigniter ( A PHP framework ). Using codeigniter I can extend websites functionality without any problem.
4 - I am a php developer and I don't know much about assets pipeline, but I have googled it and I think it is for ruby on rails. I am sorry I don't know this term.
5 - Animation done by CSS3 is way better than jquery in terms of performance and looks. But GSAP offers a very great frame rates for a lot of animation. Gsap is a plugin based on javascript. But I still prefer CSS3 because it is well known language, any one can understand it.
6 - Internet explorer 7 and 8 is an outdated browser and bootstrap is also planning to drop some compatibility in bootstrap 4. But I can use jquery plugin like modernizr to support IE7 & IE8.
7 - I will show you a mockup with improvements in design.
Sorry for short answers because of word limit. Looking forward Thank you