Po­si­ti­ve points..



I liked the part about../how you...

It was in­te­resting that...

I was im­pres­sed by...





Ma­king sug­ges­ti­ons..



I think you could/ should/ might want to...

I think it would be bet­ter to../hel­pful if../cle­a­rer if...

One idea/ pos­si­bi­li­ty/ op­ti­on is...