Sounds to me like you're doing it just about right. If you think about it, short of winding up in some kind of ballroom or major hall, a la Moria, you won't generally find many opportunities for extended missile weapons firing underground due to range limitations (to say nothing of poor visibility), so I'd say your experience with them is pretty much what I'd expect. I usually have them volley off an arrow/quarrel apiece, and then drop the missile weapon and ready a weapon for melee (but it's worth mentioning that one of the best killers I ever saw in a dungeon environment was a halfling with a sling...). If they get lucky and hit, great. If not, at least they can contribute the other way. Regardless though, there's no gainsaying that having a couple of good meatshields out in front let's everyone breathe easier -- and buys the archers a little more time to shoot.
If you have the leisure to rest between rooms, it's always a good idea so your team (and not just your Wizards!) can recoup some fatigue, however, if you make a habit of it, an evil DM (hint, hint) can always throw a wandering monster at you... And healing magic (whether spells or potions) and a good medic are pretty important too!
Remember that Summon spells suck the energy right out of the spellcaster (this assumes you're using TFT magic rules, though -- in Dark City's system, the drain isn't as great); Illusion spells are cheaper, but of course, can always be disbelieved... At the end of the day, your Wizards have finite resources that they have to carefully manage, even though pound for pound they are often worth their weight in gold in both combat and other activities. To put it in modernistic terms; your Wizards are your artillery, but they only have so much ammo available to shoot, and in the end, it always seems to be up to the poor bloody infantry.
Also, don't forget that some skills aid in perceiving things; I always try to make sure that my players have a couple of those skills in the party to facilitate finding and noticing things. Also, when you're actually running your players through, don't forget "the Three Clue Rule" (always put in multiple ways for the players to find the clues they need to progress so that the whole adventure doesn't derail simply because no one ever thought to read the scrap of paper underneath the desk, or check the pockets of the corpse -- for example, they can capture a prisoner and learn something they missed earlier that way; of they can find some graffitti on the wall that mentions something important was back in the ruined refectory).
Finally, and, most importantly, make sure everyone has fun! Some of the most talked about adventures my crews have gone through over the past thirty years have been the ones where the wheels came completely off and they (and I, as the GM) had to do extreme, insane things to get through; but if they're still talking about them three decades later, I think you can chalk that one up in the "win" column despite the "failure" of the scenario! ;-)
From: Nathan Easton <firstname.lastname@example.org>
Sent: Sunday, October 16, 2016 1:06 PM
Subject: Programmed Adventures
So, in preparation for running a TFT PBP on RPGnet, I worked my way through one of the sample adventures on Dark City Games' website.
I've essentially never played TFT, and have instead appreciated it on a theoretical level. So I'm working the kinks out before players have to put up with me.
A few thoughts:
Combat is more predictable than Classic D&D, but not by lots. The worm can turn on you real quick.
Summon/Illusion spells are essential. Much like the Summon spells in the ACKS players guide, disposable cannon fodder is a game-changer.
I let my wizard regain fatigue between rooms. Not sure if that's the way to handle it, but it seemed consistent with TFT, and I was using those rules instead of the DCG ones.
Bows seemed less useful than they should be because of the size of the rooms, and it taking a whole round to switch weapons. Maybe I'm doing something wrong here? I felt like I'd have been better off to switch my archer for another dedicated melee fighter and just hammered things down.
The Sorcerers Manor requires an IQ check about every single room to find an item vital for the endgame. It's surprisingly complicated for a free solo adventure. Point is, take one wizard with a crazy high IQ just so you don't miss half the adventure. DCG's rules are way kinder to wizards with high IQ and crap for other stats, in some ways, but you can probably pull it off in regular TFT if you're careful.