i suppose it will jus sound louder and more bass for E5. SQ wise i do not believe it would increase much.
LOD will better utilise your amp compared to mini to mini.
whether your se115 benefit from an amp is more important. so u may consider a IEM upgrade. some IEMs will only bloom with certain amps and (cables even)?
coming to this forum will you jus make you "throw" that "budget" thought away. it happen to me.