Any constant time reference is useful. But only as a reference. Playing to a metronome or a sequencer does not make playing mechanical and cold. It simply gives you a reference of solid predictable time. When playing in a group (especially a new one) solid predictable grooves and feels are very useful. They allow the audience to concentrate on the music and not be distracted by the "blurred" grooves. Get a sequencer is metronomes are boring but do practice for a large proportion of your time using a good solid reference (ie: a machine not a human). I do not mean that in any negative sense. It is simply the case that people feel and interpret tempo. Even the most even of players. When practicing you want to develop an appreciation of constant time. Then, when performing you will be conscious of speed changes (both up and down) and this consciousness empowers you to do something about it or let it happen. If you are not conscious of speed, groove and feel (to a high degree) you have less control of your music and your ability to express yourself in a concise and clear manner is reduced.

Some say instinct and inspiration are the key to expression. They are definitely part of it but the conscious mind is also necessary. Especially in group.

Lets face it. Without conscious rational thought we would not have the instruments, the musical structure, and the audiences and venues and recording systems that music relies on.

As they say it is 10% inspiration and 90% perspiration.

Use a drum machine, a metronome, a sequencer as a tool to show you what is a constant rhythm. Work on cross rhythms against the beats in the machine. Work on syncopating the rhythms. Make up exercises for yourself so that you do not practice what you already know. Polyrhythms too are very useful rhythmic devices. Rhythm is a universe of technique. Start now.