I would say Lore bard or Glamour, if you are going for Lore bard perhaps focus on more wizard, sorcerer, and druid spells. You get extra spells from any class spell list which can allow you to pick up bits from other classes like Haste as a good example. This may seem redundant but maybe take Magic initiate feat for Warlock and pick up Eldritch blast and hex as extra spells you have access to. Lore bard is best as a diverse class, they also can help you fill in skill proficiencies that nobody else in the group has.
Glamour has a pretty handy ability at 3rd that lets ou give your team some temporary hitpoints before battle or during it. Maybe distract a room full of people by talking your way in and use their enthralling music to temporarily charm them. Then when they are distracted the rest of the team either avoids them or prepares to launch the ambush.
I tend to avoid multiclassing because I am admittedly snobbish, but taking a couple levels in warlock can be a good option if you either can't take feats or really need the stat boosts.
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"Where words fail, swords prevail. Where blood is spilled, my cup is filled" -Cartaphilus
"I have found the answer to the meaning of life. You ask me what the answer is? You already know what the answer to life is. You fear it more than the strike of a viper, the ravages of disease, the ire of a lover. The answer is always death. But death is a gentle mistress with a sweet embrace, and you owe her a debt of restitution. Life is not a gift, it is a loan."
I think it depends on what you want to focus on with your bard. I also would go for Lore If you want to focus on support. If you want to be a Killer with a crossbow go for college of swords. If you manage to get your hands on the crossbow master and Sharpshooter Feats, probably also elven accuracy, you will Play DnDs Billy the Kid plus you still have good support options...
If you want to actually be good with the crossbow? Then I would suggest Valor bard. Its the only subclass that gives you Extra Attack. Otherwise? You're better off using Vicious Mockery - while low on damage, the extra ability to inflict disadvantage is a huge life saver, and at higher levels, you'll be doing more damage with it than your one shot out of crossbow. As well, using Vicious Mockery allows you to focus on raising Charisma, which increases the number of Inspirations per rest, which is another source of your support.
Alternatively, since crossbow expert would be a bit of a feat tax to get two shots per turn with crossbow, you could take the lower damage die of a longbow. You'd still get two shots per turn at lvl 6 as a valor bard, and that ASI/feat opportunity.
Aside from that everyone else has pretty much covered it. Go Valor if you want to support party DPS, or Glamour or Lore for for some party survival.
Glamour is a lot of fun from a roleplay standpoint and the ally buffs you give out are pretty decent. If you want consistant damage I'd say multi into a warlock for two levels, grab eldrict blast cantrip and agonizing blast invocation, and you'll be able to blast targets for 1d10+CHA as your action. As you level you'll get more attacks giving you the range support with being SAD. Bonus points if the patron is an archfey who taught you how to be a glamour bard.