I've got experience of modding android devices from around 2012, when i rooted Huawei U8800 and flashed CWM on it. Since then i have unlocked/modded the following phones: Samsung S4 Plus, Honor 5C, Oneplus One, ZTE Blade, Samsung Galaxy S3 Mini, Honor 5X. About half of them i have used tools such as Fastboot to unlock bootloader and flash a custom recovery.
I hope to hear from you, so we can discuss more.