With RTW, pause is mandatory for 95% of us. Once you learn to work around the speed and interface problems of RTW you can have more satisfctory battles. Once you start to understand how to use the controls and set up (and apparently not as it was intended by the programmers) you can start fighting battles as less of crazed mish mash.
When to use pause: 1. For initial set up and grouping for march 2. For initial engagement of the lines in melee. 3. Too counter the insane friendly fire/fire at will and skirmish behaviour. 4. To respond to any super fast developing part of the battle. 5. To go from 2x or 3x back to normal speed--the other keys often don't work when you try to "press" them, but pause does.
One of the problems with RTW is that if you try to order a bunch of individual attacks by units as the lines close, all the units seem to go into a criss cross mess. This is caused by the lead computing. Everyone tries to "plot an intercept" course and you get either a furball mob fight, or a disjointed set of clusters racing apart. The AI is real bad about crossing its own lines as the battle lines close. I use the drag control approach to counter this. I will click on the unit cards I want (holding CTRL to select them) and then use a mouse drag to align them as desired (the little pink arrows show how they will be positioned.) This works well for organizing a battle line and I often do it in "pause." Actual grouping can be a bit buggy so I use it sparingly. I wait for the lines to be very close before pausing and ordering individual charge or attack (usually a countercharge) vs. the facing enemy units. I can often use CTRL-A to group my army when I have it arranged like I want, then use the drag approach to march it into the location and facing I need somewhere on the field.
Phalanx units are a bit different. There is a good thread to be found in the index about using them. I use a grouped line and order them as a group to "march past" the enemy line (with guard mode disabled.) They seem to engage well like this. (Works some for other sword or spear melee as well--although you need to charge at the end with individual units.) If I order individual attack too soon the phalanx units will turn and twist and expose their flanks instead. Often I don't even order the individual attacks since they will engage on their own. The AI is clueless when it employs phalangites and rarely organizes them into a proper line, and never maintains one if it does. March them with phalanx off. Turn it on just before lines engage. Charge does nothing other than work as "attack" while in phalanx, regular attack works fine.
Keep skirmishers missiles out in front or else friendly casualties will be really bad. Often some AI unit will charge them (all to often the AI general...oh well.) When that happens hit pause, turn off fire at will, hit "stop", then order them to run behind your line. Otherwise they will stand somewhere back in your own formation or behind and pepper your own troops. Fire-at-will is borked at the moment.
Cav works best on the wings and usually in pairs or more.
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