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No, i will cause no problem.
There is no need to every day check the consistency of the DB, except for very large websites.
About clearing sessions, if you are the only one to connect to your website, there is no need to clear every day
About cache, and templates_c, clear theme daily only if you have hig traffic and plenty of accessed content's pages
Moreover, there are other parameters to set to improve your website speed display : image optimization, css/html optimization, etc., gzip. About this latest one, i've reported yesterday a bug, and i've noticed too it slowed my website.
Do synergy or die.