In my year so far I have yet to learn tsurikomi goshi. I feel like I missed something now.
The best chances I have had with harai goshi have been when I can use my long stride (I am taller than average) to angle off and find kazushi from uke having to try and "catch up". They often end up leaning forward nicely so I can fit in. It mostly only works on fellow beginners though, and my harai goshi isn't great.
Its better than my tai otoshi though. Yeesh.