As I have talked about here in a bit more detail, I have always had an issue wrapping my head around certain core (and simple) concepts within D&D 5e. In this particular case, the issue pertains to picking the right weapon for a build, beyond the simpler "longsword and a battle axe are the same things with different flavour" answers, such as why one would pick a mace over a greatclub as they both do the same amount and type of damage. I've tried asking the community in a few different ways getting either very specific answers pertaining to the weapons I've exampled, all the way to having my questions closed for being too vague, opinion-based, or confusing.
I've recently compiled all my data into an easy, clear, and concise form answering my concerns, and I wanted to share it with the community as a free resource for anyone who's been having/will come here having the same issue. However, Thomas Markov wisely pointed out that even the best answer can have issues if it doesn't proceed with a clear and concise question, which he suggested I workshop both first (and here I am).
What are the basic aspects to look for when deciding on your character's initial weapon? >Aside from the flavouring, such as between the 1d8 slashing damage of a longsword and battle axe, what other factors would come into consideration when choosing from among the weapons you're proficient in?
There are quite a bit of factors to consider, such as any class and subclass bonuses you might get by favouring a certain kind of weapon, but I find a great place to start is by considering what kind of character you want to play and what modifiers are available to you during character creation.
Where you want to position your character in battle becomes rather important, as it will heavily determine what kinds of options are available to you; Frontline fighters tend to gravitate towards the bulkier weapons as they focus on taking a hit and dishing it right back, whereas midline fighters often focus on fineness and one-handed weapons as it keeps them more versatile and utilitarian, back-line fighters focus on ranged attacks and taking that perfect shot, while spellcasters focus on staves as they double as a spellcasting focus.
From there, you can gather all the ways to add a modifier to your roll. While there are class features like Sneak Attack or Hex Warrior that might limit/alter your choices (but often comes at a bonus to damage), I find that there are 3 major categories of basic modifiers that you'll be dealing with going up from level 1 to level 4:
Proficiency and Ability Scores: From among the weapons you are proficient in, each one will be influenced by either your Strength modifier or Dex modifier for Fineness and Ranged weapons. For example, a level 1 fighter with 16 Strength and 15 Dexterity can add a +5 to their longsword attack rolls and +4 to their longbow attack rolls. Note, proficiency only applies to attack rolls and not damage rolls. However, there are a few ways that a character might base their attacks on a different ability score, which Groody the Hobgoblin and User2754 have kindly listed, however they would be subjected to the same application of proficiency + ability mod.
Feats and Fighting Styles: While maintaining a theme (such as polearms, ranged, or bludgeoning) here can make for a rather powerful build, this too can add quite the outlier to your choices and each deserves their own consideration. For instance, a fighter might choose to compliment their Halbert with Great Weapon Fighting and Great Weapon Master to become a heavy hitter, while a ranger might opt to accent their druidic staff with Dueling, and Polearm Master for better area control.
Magic Weapons: While it won't be likely that a DM will grant you a +1 sword from the start, it is important to remember that +1, +2, and +3 weapons of all kinds exist in D&D, and even the most basic of models are considered magical and add the modifiers on top of all those you gain with their non-magical copies.
There are also weapons that break the rolls between two dice. While it won't affect the max damage between, say, a greataxe and a greatsword, it does affect the probabilities you might wish to achieve: single dice have a higher chance to roll max damage, but the double dice roll average damage more frequently.
As a final bit of help, below you'll find a chart listing all the weapons available, what dice they use, and the average damage you can expect to gain from them with modifiers up to a +10. You can use it to compare different combinations of weapons and modifiers available to you to get a better understanding of what you can expect and maybe discover new combinations that will work better for you.
|Club, Dagger, Dart, Hooked Shortspear, Light Hammer, Sickle, Sling, Whip||1d4||2.5||3.5||4.5||5.5||6.5||7.5||8.5||9.5||11||12||12.5|
|Hand Crossbow, Handaxe, Hoopak, Javelin, Mace, Quarterstaff (single), Scimitar, Shortbow, Shortsword, Spear (single), Trident (single)||1d6||3.5||4.5||5.5||6.5||7.5||8.5||9.5||11||12||13||13.5|
|Greatsword, Maul, Oversized Longbow||2d6||7||8||9||10||11||12||13||14||15||16||17|
|Battleaxe (single), Flail, Greatclub, Light Crossbow, Longbow, Longsword (single), Morningstar, Quarterstaff (Dual), Rapier, Spear (dual), Trident (dual), War Pick, Warhammer (single), Yklwa||1d8||4.5||5.5||6.5||7.5||8.5||9.5||11||12||13||14||14.5|
|Battleaxe (dual), Glaive, Halberd, Heavy Crossbow, Longsword (dual), Pike, Warhammer (dual)||1d10||5.5||6.5||7.5||8.5||9.5||11||12||13||14||15||15.5|
|Great Weapon Master|
|Greatclub, Morningstar, Quarterstaff (Dual), Spear (dual), Trident (dual)||1d8||5.5||6.5||7.5||8.5||9.5||11||12||13||14||15||15.5|
|Battleaxe (dual), Glaive, Halberd, Longsword (dual), Pike, Warhammer (dual)||1d10||6.5||7.5||8.5||9.5||11||12||13||14||15||16||16.5|
ALTERNATIVE If the question I posed seems off, then would there be a feasible way to share this chart?