@Eddie-R the contact list could easily be used to track individuals both members and guests. You could have a system for following up with guests that is tracked and could assign different people tasks related to that follow-up, which is a sweet spot for Disciple.Tools. You could send all your members a periodic request for them to update their records with the magic link feature. I'd set each small group up in the groups record type and you can add the members of the small groups to each and designate the leader for each. Tracking attendance is less of a primary feature for Disciple.Tools, but like @Corsac mentioned, it could possibly be done through the Meetings plugin.
Many tools could meet the needs of your use case. Disciple.Tools will stand out the more that you're collaborating and collecting information from multiple people.