There are several options that look more at the hashkafic side of proper speech and not the halachos per se.
Looks at how to use speech in a positive manner. Using refined language and avoiding nivul peh. The blurb there reads:
A defining characteristic of man.
An empowering method through which we can meaningfully communicate with each other and with our Creator.
The tool through which we can bestow tremendous blessing-or, chas v'shalom, the opposite.
It all depends on how well we maintain our spiritual oral hygiene.
In Sparkling Speech, noted mechanech and author Rabbi Elysha Sandler explores the topic of permissible speech and nivul peh, as it pertains to us today. Drawing upon extensive sources, Rabbi Sandler presents a thorough examination of this important topic, including engaging stories, as well as ideas and methods for how we can all improve our speech.
Well-written and practical, this sefer will provide you with much chizuk and inspiration in the area of refining our language.
Positive Word Power by the Chofetz Chaim Heritage Foundation
Provides scenarios and related strategies for engaging in positive speech
Talk is NOT cheap.
Words are our most valuable - and most powerful - assets. Through words, we can forge or tear down relationships, inspire or demean our children, spouses, or friends, offer comfort or inflict pain. Through words, we can create an atmosphere of harmony or discord, contentment or conflict, blessing or, Heaven forbid, its opposite.
Controlling and properly channeling our words can seem as impossible as stopping a rushing river.
But the Torah teaches us that we can control what we say.
The Chofetz Chaim taught us how to incorporate the laws of shmiras haloshon into our daily lives. Positive Word Power, based on Rabbi Zelig Pliskin's classic The Power of Words, focuses on ona'as devarim, -- the hurtful speech we all too often use in our direct, daily interaction with others. This original work examines dozens of true-life situations in which the wrong words can wound people, damage friendships and ignite hostility. More importantly, it offers concise, practical strategies for controlling destructive speech and for communicating with others in ways that nurture and build.
Just as our acclaimed bestseller, The Chofetz Chaim: A Daily Companion, is showing tens of thousands around the world how to tap into the profound wisdom of the Chofetz Chaim through a simple daily program, designed to help us avoid negative speech about others, Positive Word Power aims to awaken and sensitize us to the critical importance of being careful how we speak to others.
This is a book that will enrich and, ultimately, transform your relationships and your life.
There is also Rabbi Zelig Pliskin's Guard Your Tongue - whilst this is an English version of the Chofetz Chaim's Shemiras HaLoshon which I know you don't want, this is worth viewing though, as it also includes life examples which helps to frame the scenarios and how to practically apply these laws.
Finally for a more mussar-led approach to lashon hara I would look at the 25th Chapter in Orchos Tzaddikim which is dedicated to lashon hara