Más a menudo means more often.
Breakdown:
So:
It is a very natural expression in Spanish.
The accent mark shows where the stress goes: de-be-rí-a-mos.
In the conditional tense, the endings have a written accent:
So:
The accent helps show the correct pronunciation and is part of the standard spelling.
For this meaning, normally no.
In standard Spanish, especially in careful usage:
So in your sentence, Deberíamos hablar is the right form.
A simple pronunciation guide is:
de-be-rí-a-mos a-blar mas a me-nu-do
A few useful points:
A rough English-friendly version could be:
deh-beh-REE-ah-moss ah-BLAR mahs ah meh-NOO-doh
Usually it sounds like a suggestion: we should talk more often.
But tone and context matter. Depending on how it is said, it could sound:
For example, after not seeing someone for a long time, it often sounds warm and natural rather than forceful.
It is the first person plural conditional of deber.
Person and number:
Conditional formation:
So:
This is why it means we should / we would have to / we ought to, depending on context.