最近イオシスで購入したものです。
root化は勇気が無いので先ずはドコモアプリの削除等を行いました。

adb shell pm uninstall -k --user 0 com.android.contacts
adb shell pm uninstall -k --user 0 com.huawei.d01j.manual

adb shell pm uninstall -k --user 0 com.nextbit.app
adb shell pm uninstall -k --user 0 com.nttdocomo.android.accountauthenticator
adb shell pm uninstall -k --user 0 com.nttdocomo.android.accountwipe
adb shell pm uninstall -k --user 0 com.nttdocomo.android.anmane2
adb shell pm uninstall -k --user 0 com.nttdocomo.android.apnsw
adb shell pm uninstall -k --user 0 com.nttdocomo.android.applicationmanager
adb shell pm uninstall -k --user 0 com.nttdocomo.android.areamail
adb shell pm uninstall -k --user 0 com.nttdocomo.android.atf
adb shell pm uninstall -k --user 0 com.nttdocomo.android.bugreport
adb shell pm uninstall -k --user 0 com.nttdocomo.android.cloudset
adb shell pm uninstall -k --user 0 com.nttdocomo.android.databackup
adb shell pm uninstall -k --user 0 com.nttdocomo.android.dcmvoicerecognition
adb shell pm uninstall -k --user 0 com.nttdocomo.android.devicehelp
adb shell pm uninstall -k --user 0 com.nttdocomo.android.dhome
adb shell pm uninstall -k --user 0 com.nttdocomo.android.dmenu2
adb shell pm uninstall -k --user 0 com.nttdocomo.android.docomoset
adb shell pm uninstall -k --user 0 com.nttdocomo.android.homeagent
adb shell pm uninstall -k --user 0 com.nttdocomo.android.iconcier
adb shell pm uninstall -k --user 0 com.nttdocomo.android.iconcier_contents
adb shell pm uninstall -k --user 0 com.nttdocomo.android.idmanager
adb shell pm uninstall -k --user 0 com.nttdocomo.android.initialization
adb shell pm uninstall -k --user 0 com.nttdocomo.android.mascot
adb shell pm uninstall -k --user 0 com.nttdocomo.android.mediaplayer
adb shell pm uninstall -k --user 0 com.nttdocomo.android.osv
adb shell pm uninstall -k --user 0 com.nttdocomo.android.pf.dcmippushaggregator
adb shell pm uninstall -k --user 0 com.nttdocomo.android.pf.dcmwappush
adb shell pm uninstall -k --user 0 com.nttdocomo.android.remotelock
adb shell pm uninstall -k --user 0 com.nttdocomo.android.schedulememo
adb shell pm uninstall -k --user 0 com.nttdocomo.android.screenlockservice
adb shell pm uninstall -k --user 0 com.nttdocomo.android.sdcardbackup
adb shell pm uninstall -k --user 0 com.nttdocomo.android.socialphonebook
adb shell pm uninstall -k --user 0 com.nttdocomo.android.store
adb shell pm uninstall -k --user 0 com.nttdocomo.android.voiceeditor
adb shell pm uninstall -k --user 0 com.nttdocomo.android.wipe
adb shell pm uninstall -k --user 0 jp.co.nttdocomo.anshinmode
adb shell pm uninstall -k --user 0 jp.co.nttdocomo.bridgelauncher
adb shell pm uninstall -k --user 0 jp.co.nttdocomo.carriermail
adb shell pm uninstall -k --user 0 jp.co.nttdocomo.lcsapp
adb shell pm uninstall -k --user 0 jp.co.nttdocomo.lcsappsub
adb shell pm uninstall -k --user 0 jp.co.nttdocomo.saigaiban
adb shell pm uninstall -k --user 0 jp.co.omronsoft.android.decoemojimanager_docomo