"one is ... another is ... " and "the first is ... the second is ...."

I am writing an academic paper. I use the following representations:

However, up to now, far too little attention has been devoted to two
problems of the state-of-the-art proof automation systems. One is …
Another is …

Somebody advises me to use

However, up to now, far too little attention has been devoted to two
problems of the state-of-the-art proof automation systems. The first is …
The second problem is …

Does the reason come from that "The first is … The second problem is …" is more formal, or
more clear?

Thanks in advance!