I often send small amount of Bitcoin around 100,000 satoshi, is there a way to avoid paying a fee that is a significant proportion of the amount sent?
Yes, register/adopt to a new wallet service that has very less to no transaction fee for making sending bitcoins.
With XAPO you need not to pay any fee. With bitcoin-qt or bitcoin core wallets you can set fees to zero, but not sure when your transactions will be included in blocks to get conformations.
Sometimes the minimum transaction fee is 0.0001
BTC I can't think of anything that could be lower than that.