You have asked me for some advice on how to improve … I will try to give some useful suggestions.
You asked for advice concerning (with regard to)… and I will try to make some suggestions.
I have received your letter saying… I recommend that…
I am writing to you to present what I think on the further improvement of…
I am writing in reply to …
I am writing to express my views about …
I would like to suggest that…
I would recommend that…
I hope that my suggestions are helpful for your decision-making anyway.
I would be more than happy to see improvement in this regard.
Thank you for your attention.
I believe that you will take my suggestions into serious account.
Please take good consideration of my advice. Thank you.
I hope you find these suggestions/proposals practical.
I would be ready to discuss about this matter with you to further details.
Whatever you decide to do, good luck with your studies/work!
I feel that it would be beneficial if…
If I were you, I would…
You may consider doing…
It would seem to me that you could…
As you may agree that…