Use gmail/google as your email service provider should solve part of the issues as it will be white listed across many providers at that point.
You can also look at
https://www.senderscore.org
There are other tools you can use to check if the contents of the email are what is flagging the spam filter.. (link or text you email sig etc...)
You can check the MQS Score
http://info.contactology.com/check-mqs